Blog
Practical guides for everyday conversions, and honest explainers on how online tools handle your data.
Posts are contributed and editorially reviewed, corrections and suggestions welcome via the contact page.
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Finance · how-to
Is Refinancing Worth It? How to Find Your Mortgage Break-Even Point
Mortgage refinance break-even = closing costs ÷ monthly savings. How to find the month refinancing pays off, and the longer-term trap a lower payment hides.
2026-08-23
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Size Converters · explainer
Paper Sizes Explained: A4 vs Letter, and Every Size in mm, Inches and Pixels
A4 is 210×297 mm; US Letter is 215.9×279.4 mm, not interchangeable. Every ISO, US and ANSI size in mm, inches, points and pixels, plus the 1:√2 ratio.
2026-08-23
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Text Tools · explainer
Text to Speech in Your Browser: How It Works (No Upload, No Account)
Browser text to speech reads text aloud with your device's built-in voices, no account, no upload, offline for local voices. Here's how it works.
2026-08-06
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Productivity · explainer
How to Pick a Fair Random Winner (Names, Raffles and Giveaways)
Picking a random winner by hand is rarely fair. What fair selection means, when to draw with or without replacement, and how to spin one locally.
2026-08-06
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Productivity · explainer
An Online Notepad That Saves in Your Browser (Not the Cloud)
An online notepad that saves in your browser with localStorage, not the cloud. How local autosave works, why it's more private, and its storage limits.
2026-08-06
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Productivity · explainer
How to Test Your Webcam and Mic Before a Call (Privately)
Test your webcam and mic before a call: check your camera preview and microphone level meter in the browser, privately, with nothing recorded.
2026-08-06
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File Converters · explainer
What's Inside an MP4 File? Boxes, Atoms and the 'moov' Problem
What's inside an MP4? A tree of boxes (atoms) like ftyp, moov and mdat. How the structure works, why a misplaced moov box breaks playback or streaming.
2026-08-05
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Audio & Video · explainer
FLAC vs MP3 vs WAV: Three Formats, Three Ways to Store Tags
FLAC vs MP3 vs WAV: how each stores tags (Vorbis comments, ID3, RIFF chunks), how to check if a FLAC is really hi-res, all in your browser.
2026-08-04
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File Converters · explainer
How Google's Encoded Polyline Algorithm Works (and How to Decode One)
A Google encoded polyline is a compact string of coordinates. How the algorithm works step by step, the precision and lat/lng gotchas, and how to decode one.
2026-08-04
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Image Tools · explainer
Inside a PNG File: Chunks, CRCs and Hidden Metadata
A PNG is a signature followed by labelled chunks, each with a CRC-32 to catch corruption. How the format is structured and where hidden metadata lives.
2026-08-04
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Developer Tools · explainer
What Is a JWK Thumbprint? Stable Key IDs the RFC 7638 Way
A JWK thumbprint is a reproducible fingerprint of a JSON Web Key, used as its kid. How RFC 7638 computes it and how to generate one in your browser.
2026-08-04
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Developer Tools · explainer
How to Decode a Protobuf Message Without the .proto Schema
Decode a Protocol Buffers message without its .proto file, the wire format is self-describing. How protobuf encoding works and how to read a raw message.
2026-08-03
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Developer Tools · explainer
How to Read Email Headers and Trace a Message's Path
Email headers show which servers handled a message and whether it passed SPF, DKIM and DMARC. How to read them, spot a spoof, and trace the path.
2026-08-03
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Audio & Video · explainer
ID3 Tags Explained: How MP3 Metadata Actually Works
ID3 tags hold an MP3's title, artist and album. How ID3v1 and ID3v2 differ, why tags show garbled text, and how to read any MP3's tags in-browser.
2026-08-03
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Audio & Video · explainer
Sample Rate, Bit Depth and the WAV File Format Explained
Sample rate and bit depth explained: what 44.1 kHz, 16-bit mean, how the RIFF/WAVE format stores them, and how to read a WAV header.
2026-08-03
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File Converters · explainer
What Is an EPUB File? A Look Inside the E-book Format
An EPUB is really a ZIP of web pages plus a metadata file. Here's how the format is structured, container.xml, the OPF package, Dublin Core metadata and the spine, and how to read any EPUB's title, author and ISBN in your browser.
2026-08-03
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Developer Tools · explainer
What Is CBOR? Binary JSON for Passkeys, COSE and IoT, Explained
CBOR is a compact binary format like JSON, used by passkeys, WebAuthn and IoT. How CBOR encoding works, diagnostic notation, and how to decode it.
2026-08-03
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File Converters · explainer
What's Inside a .torrent File? Bencode, the Info-Hash and Magnet Links
A .torrent file holds no content, just bencoded metadata plus the info-hash that identifies the torrent. How it's structured and how to read one.
2026-08-03
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Developer Tools · explainer
Why 0.1 + 0.2 Isn't 0.3: IEEE 754 Floating-Point Explained
Type 0.1 + 0.2 into almost any programming language and you get 0.30000000000000004. Here's why, how IEEE 754 stores numbers as sign, exponent and mantissa, why most decimals can't be exact, and how to see the bits yourself.
2026-08-03
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File Converters · explainer
WKT vs GeoJSON: Two Ways to Write a Geometry (and How to Convert)
WKT vs GeoJSON: both describe points, lines and polygons, but one is compact text for databases and one is JSON for web maps, plus how to convert.
2026-08-03
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Developer Tools · explainer
Base64 vs Ascii85 vs Base62: Which Binary-to-Text Encoding Should You Use?
Base64, Ascii85 and Base62 turn binary into text with different size and URL-safety trade-offs, how each works and when to use which.
2026-08-02
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Developer Tools · explainer
Check Digits Explained: How Barcodes, ISBNs and Card Numbers Catch Typos
A check digit is an extra digit computed from the rest of a barcode, ISBN or card number to catch typos, how mod-10, mod-11 and Luhn work.
2026-08-02
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Travel & Trips · explainer
GPS Coordinate Formats Explained: DD, DMS, UTM, MGRS and Geohash
GPS coordinate formats explained: decimal degrees, DMS, UTM, MGRS and geohash, what each is, who uses it, and how to convert between them.
2026-08-02
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Privacy & Security · explainer
How to Read an X.509 SSL Certificate: Every Field Explained (PEM, DER and ASN.1)
Read an X.509 SSL certificate: it decodes into readable fields, subject, issuer, validity, public key and SAN domains. What each means, decoded locally.
2026-08-02
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Generators · explainer
How .ics and .vcf Files Work: Calendar Events and Contacts Explained
.ics and .vcf files are the plain text behind calendar events and contacts, how iCalendar and vCard work, the all-day end-date gotcha, done in your browser.
2026-08-02
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Image Tools · explainer
DPI Explained: How to Set an Image to 300 DPI Without Losing Quality
Image DPI is a print-time metadata tag: setting it to 300 DPI is lossless, resampling is not. What DPI really means and how to set it in your browser.
2026-08-02
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File Converters · explainer
INI vs .env vs .properties: Three Config Formats Explained (and How to Convert Them to JSON)
INI, .env and Java .properties all store key=value config with different rules. How each works and how to convert any of them to JSON in your browser.
2026-08-02
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Privacy & Security · explainer
Magic Bytes: How to Tell a File's Real Type (Not Its Extension)
A file's real type lives in its first few bytes, the magic number, not its extension. How file signatures work and why a .pdf can secretly be an .exe.
2026-08-02
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Developer Tools · explainer
What Is a Snowflake ID? How Discord and Twitter Hide a Timestamp in Every ID
A Discord or Twitter/X ID is a 64-bit Snowflake with the creation time baked in, how the bits are laid out, why the epoch matters, and how to decode one.
2026-08-02
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Fonts & Typography · explainer
What's Inside a Font File? TTF and OTF Metadata Explained
A .ttf or .otf font is an sfnt file: a directory of tables holding name, version, glyph outlines and embedding licence. What each stores, read in your browser.
2026-08-02
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File Converters · explainer
Why Your SVG Files Are Bloated, and How to Optimize Them Safely
SVGs from Illustrator or Figma are often 2-5× too big, full of editor metadata and extra precision. What the junk is and how to strip it losslessly.
2026-08-02
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File Converters · explainer
How to Zip and Unzip Files in Your Browser (No Software, No Upload)
You don't need WinRAR or 7-Zip to make or open a ZIP, a browser does both locally. How ZIP works and how to zip or unzip without uploading anything.
2026-08-02
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Statistics · explainer
Is Your A/B Test Result Real? Significance, p-values and Effect Size
A/B test significance needs a small p-value AND a meaningful effect size, not just a green badge, how z-tests, p-values and Cohen's d fit together.
2026-08-01
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Calculators · explainer
Blood Sugar Units Explained: mg/dL, mmol/L, HbA1c and eAG
Convert blood sugar units: divide mg/dL by 18.0182 for mmol/L, and see how HbA1c %, mmol/mol and estimated average glucose all connect.
2026-08-01
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Developer Tools · explainer
How to Convert a curl Command to JavaScript fetch()
Convert a curl command to JavaScript fetch(): -X becomes method, each -H a headers entry, -d the body, the full mapping and gotchas.
2026-08-01
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Date & Time · explainer
What Day of the Year Is It? Ordinal Dates and Leap Years Explained
The day-of-year is the ordinal count from January 1: day 60 is March 1, day 61 in a leap year. How ordinal dates, leap years and business days work.
2026-08-01
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File Converters · explainer
How to Convert a File to a Base64 Data URI (and Back)
A Base64 data URI embeds a whole file as text, data:<mime>;base64,<data>, so you can inline it in HTML, CSS or JSON with no separate request.
2026-08-01
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Developer Tools · explainer
How to Generate SQL INSERTs from JSON or CSV (Safely)
Convert JSON or CSV to SQL INSERTs correctly: type each value, escape single quotes by doubling, and parse CSV per RFC 4180, all in your browser.
2026-08-01
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Developer Tools · explainer
Generate Typed Models from JSON: TypeScript, Go, Python, Rust & C#
Turn a JSON sample into typed models, a TypeScript interface, Go struct, Python dataclass, Rust struct or C# class. How the mapping works, in your browser.
2026-08-01
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File Converters · explainer
GPX Files Explained: Distance, Elevation and Converting to GeoJSON
A GPX file is XML listing GPS track points. How distance and elevation are calculated, the lat/lon trap when converting to GeoJSON, and doing it in your browser.
2026-08-01
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PDF Tools · explainer
How to Compress a PDF Without Losing Quality
Compress a PDF without losing quality: lossless compression re-encodes the file's data streams so text stays selectable and images keep their exact pixels.
2026-08-01
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Statistics · explainer
Which Statistical Test Should I Use? A Decision Guide
t-test, z-test, ANOVA, Mann-Whitney or chi-square? The right test depends on your data type, how many groups you have, and whether it's normal. Here's a simple decision path, with calculators that run in your browser.
2026-08-01
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Developer Tools · explainer
Base32 vs Base64: What's the Difference?
Base32 vs Base64: Base32 is case-insensitive and easy to type; Base64 is more compact. When to use each, and encode or decode in your browser.
2026-07-28
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Calculators · explainer
How to Calculate BMI and What It Means
BMI = weight(kg) ÷ height(m)², 70 kg at 1.75 m is 22.9. The formula, WHO ranges, and its limits, computed in your browser, health data never uploaded.
2026-07-28
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Fitness & Exercise · how-to
How Many Calories Did I Burn? (MET Formula)
How many calories did I burn? Per minute it's MET × 3.5 × weight(kg) ÷ 200, the ACSM formula. Estimate walking, running or cycling free, in your browser.
2026-07-28
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Calculators · explainer
How Much Does It Cost to Run an Appliance? (Watts to Dollars)
An appliance's running cost is its power in kW times hours used times your price per kWh, the formula, worked examples, and why fridges cost less.
2026-07-28
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File Converters · how-to
How to Convert Excel to JSON (in Your Browser)
To convert Excel to JSON, the first row becomes the field names and each row becomes an object, an array of objects. Done locally, never uploaded.
2026-07-28
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Home & DIY · how-to
How Many Boxes of Flooring Do I Need?
How many boxes of flooring do I need? Add a waste allowance to your room area, divide by the coverage per box, and round up. Free calculator in your browser.
2026-07-28
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Calculators · how-to
How to Calculate Your GPA (Grade Points & Credits)
GPA = Σ(grade points × credit hours) ÷ Σ(credit hours) on the 4.0 scale. Worked examples, weighted vs unweighted, and the grade-you-need formula.
2026-07-28
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Privacy & Security · how-to
How to Hash a Password with Bcrypt
To hash a password with bcrypt: pick a cost factor (10-12), hash, and store the whole $2b$ string, salt included. Runs in your browser; never uploaded.
2026-07-28
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Calculators · how-to
Hourly to Salary: What You Earn Per Year
Annual salary = hourly rate × hours/week × 52. $25/hr at 40 h → $52,000. Convert any wage to yearly, monthly or back, free, in your browser.
2026-07-28
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Developer Tools · explainer
How IBAN Validation Works (the Mod-97 Check)
An IBAN is valid when its ISO 13616 mod-97 checksum leaves a remainder of exactly 1. How the check works, step by step, locally, never uploaded.
2026-07-28
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Calculators · explainer
How Much Protein Should You Eat Per Day?
How much protein per day? About 0.8 g/kg for general health, 1.2-1.6 if active, and 1.6-2.2 g/kg to build muscle. How to find and hit your number.
2026-07-28
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Gardening & Plants · how-to
How Much Soil Do I Need for a Raised Bed?
Soil for a raised bed = length x width x depth. An 8x4 ft bed 12 in deep = 32 ft3 (about 906 L, 1.2 yd3). Work it out free, in your browser.
2026-07-28
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Developer Tools · how-to
How to Create and Sign a JWT (HS256)
To create a JWT, base64url-encode a JSON header and payload, then sign header.payload with HMAC-SHA256 and your secret, all in your browser, never uploaded.
2026-07-28
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Image Tools · how-to
How to Crop an Image to Any Aspect Ratio
To crop an image, drag a crop box (or type an exact X, Y, width and height) over the part you want to keep and export it. Do it free, in your browser.
2026-07-28
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Image Tools · how-to
How to Make a Favicon (Every Size You Need)
Make a favicon the right way: start from one square image, export favicon.ico plus every PNG size, and add the link tags. Free, in your browser.
2026-07-28
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Privacy & Security · explainer
How TOTP (Two-Factor Authenticator) Codes Work
TOTP is the rotating 6-digit 2FA code your authenticator shows, an HMAC of the current time and a shared secret (RFC 6238). How it's built and why it rotates.
2026-07-28
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Developer Tools · explainer
How to Convert JSON to TypeScript Interfaces
JSON to TypeScript: map each value to a type, break nested objects into their own interface, and mark missing keys optional, instantly in your browser.
2026-07-28
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Fitness & Exercise · explainer
How to Measure Body Fat with a Tape (The US Navy Method)
The US Navy body-fat method estimates body fat percentage from tape measurements: neck and waist for men, plus hips for women. Measuring and accuracy.
2026-07-28
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Fitness & Exercise · how-to
How to Calculate Your One-Rep Max (1RM)
Estimate your one-rep max from a near-failure set with the Epley formula instead of risky max testing. Worked examples, %1RM by goal, free, in your browser.
2026-07-28
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Cooking & Kitchen · how-to
Oven to Air Fryer Conversion (The 25°F Rule)
To convert an oven recipe to an air fryer, lower the temperature ~25 °F and cut the time ~20%. Chart, worked example, and a free in-browser calculator.
2026-07-28
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Calculators · explainer
When Is Your Fertile Window? How to Estimate Ovulation
Your fertile window is the ~6 days ending on ovulation, which falls about 14 days before your next period. How to estimate it from your cycle length.
2026-07-28
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Home & DIY · explainer
How Many Gallons Is My Pool? (Volume by Shape)
Pool volume = surface area × average depth: length × width × depth (rectangular) or π × radius² × depth (round). Calculate gallons for any pool shape.
2026-07-28
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Generators · how-to
How to Read a QR Code From an Image (No App)
Read a QR code from an image or screenshot: paste it into a browser reader to decode the text or link. Runs locally, nothing uploaded.
2026-07-28
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Image Tools · how-to
How to Reduce Image Size to KB (Under 50 KB)
Reduce image size to KB by lowering quality and dimensions. A browser tool binary-searches JPEG quality to hit your exact target, never uploaded.
2026-07-28
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Cooking & Kitchen · how-to
Rice to Water Ratio: Perfect Rice by Type
White long-grain rice uses a 2:1 water-to-rice ratio. Brown, basmati, jasmine, sushi and wild rice each differ, get the numbers, free, in your browser.
2026-07-28
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Audio & Video · how-to
How to Convert SRT to VTT for HTML5 Video
To convert SRT to VTT, add a WEBVTT header, change the millisecond comma to a dot, and drop the cue numbers. Do it free, in your browser, nothing uploaded.
2026-07-28
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Image Tools · how-to
How to Convert SVG to PNG (at Any Size)
Convert SVG to PNG in your browser: load the SVG onto a canvas at any size and export a lossless PNG. Keep the aspect ratio and render at 2× for retina.
2026-07-28
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Cooking & Kitchen · explainer
How Long to Cook and Thaw a Turkey (By Weight)
Roast a turkey at 325°F for about 13 minutes per pound unstuffed (15 stuffed), and thaw it in the fridge about 24 hours per 4-5 pounds. Here are the timings by weight, but the only real doneness test is 165°F.
2026-07-28
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Automotive · explainer
Two-Stroke Fuel Mix Ratios Explained (50:1, 40:1, 32:1)
To mix two-stroke fuel, divide the petrol by the ratio number to get the oil, 5 litres at 50:1 needs 100 ml. Every ratio, a chart, and costly mistakes.
2026-07-28
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Electronics & Circuits · explainer
Voltage Drop Explained (and How to Keep It Under 3%)
Voltage drop is voltage lost to wire resistance: 2 × current × resistance-per-metre × one-way length (√3 for three-phase). Calculating it and the 3% rule.
2026-07-28
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Calculators · explainer
What Grade Do I Need on My Final? (The Formula)
What grade do I need on my final? needed = (target − current × (1 − weight)) ÷ weight. The formula worked out, with reachable and impossible examples.
2026-07-28
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Developer Tools · explainer
What Is HMAC? (And How to Generate One)
HMAC is a keyed hash: mix a message, a secret key and a hash like SHA-256 to get a signature only key-holders can reproduce, proving origin and integrity.
2026-07-28
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Home & DIY · how-to
What Size Air Conditioner Do I Need? (BTU)
What size air conditioner do I need? Start at about 20 BTU/h per square foot, then adjust for sun, people and kitchens. Free BTU calculator, in your browser.
2026-07-28
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PDF Tools · explainer
How to Edit a PDF Without Uploading It (Sign, Organize, Convert, Privately)
Edit a PDF without uploading it, sign, merge, split, reorder and extract text entirely in your browser, so the file never leaves your device.
2026-07-27
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PDF Tools · explainer
How to Extract Text from a PDF (Without Uploading It)
Extract PDF text in your browser, nothing uploaded, digital PDFs give up text instantly, scanned PDFs need OCR. Here's how, and why some return none.
2026-07-27
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Calculators · explainer
How to Add and Remove VAT (Without Getting It Wrong)
How to calculate VAT: add by multiplying net by 1 plus the rate, remove by dividing gross by it, not by subtracting the percentage. Worked examples inside.
2026-07-27
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Fonts & Typography · explainer
How Do Font Generators Work? (They're Not Fonts, They're Unicode)
Instagram 'fonts' aren't fonts, a generator swaps each letter for a Unicode character that looks bold or cursive. How it works and its accessibility cost.
2026-07-26
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Calculators · explainer
Aspect Ratio Explained: What 16:9 Means and How to Resize Without Stretching
Aspect ratio is the width-to-height proportion, 16:9, 4:3, 1:1, independent of pixel size. Resize without stretching and pick the right ratio.
2026-07-25
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Calculators · explainer
What Time Should I Go to Bed? Sleep Cycles, Bedtime Charts, and Why 7.5 Hours Beats 8
To wake at 6 AM refreshed, go to bed around 10:15 PM, five 90-minute sleep cycles. The bedtime chart for every wake time, plus how much sleep you need by age.
2026-07-25
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Pets & Animals · explainer
The 1 Inch Per Gallon Rule Is Wrong, What Actually Limits Fish Stocking
The 1 inch per gallon rule fails: fish waste scales with body mass, not length. What really limits stocking, adult size, bioload, surface area and filtration.
2026-07-18
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Music & Audio · explainer
BPM to Delay Time: The 60,000 Rule Every Producer Should Know
BPM to delay time: quarter-note ms = 60,000 ÷ BPM (500 ms at 120 BPM). Full subdivision table plus dotted and triplet delays explained.
2026-07-18
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Photography · explainer
Crop Factor Explained: Your 50mm Doesn't Become a 75mm (and f/1.8 Is Still f/1.8)
Crop factor is the ratio between your sensor and 35mm film. It changes framing, not the lens. Why 50mm on APS-C frames like 75mm and exposure stays put.
2026-07-18
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Weather & Atmosphere · explainer
Dew Point vs Relative Humidity: Why 100% Humidity Can Feel Fine and 50% Can Feel Awful
Dew point measures actual moisture; relative humidity depends on temperature. Why 100% humidity can feel dry and 50% can feel muggy, plus the comfort scale.
2026-07-18
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Travel & Trips · explainer
How Long Does Jet Lag Last? Why Flying East Is Worse, and How to Cut Recovery in Half
Jet lag lasts about 1 day per time zone west, 1.5 days per zone east. The circadian reason east is harder, and how timed light cuts recovery in half.
2026-07-18
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Travel & Trips · explainer
How Much Layover Time Do You Need? Minimum Connection Times vs. What's Actually Safe
Airlines allow 30-minute connections, but plan 60-90 minutes domestic and 2-3 hours international. What minimum connection time really means.
2026-07-18
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Homebrewing · explainer
IBU Explained: Why Your 60 IBU Beer Doesn't Taste Twice as Bitter as a 30
IBU measures iso-alpha acids in mg/L, but perceived bitterness depends on malt too. How the Tinseth formula works and why BU:GU predicts balance.
2026-07-18
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Astronomy & Space · explainer
Moon Phases Explained: Why There Are 8, Why They Take 29.5 Days, and Why There's No Dark Side
The Moon's phases come from the Sun, Earth, Moon angle, not Earth's shadow, the 8-phase cycle, why the month is 29.5 days, and why there's no dark side.
2026-07-18
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Home & DIY · explainer
How Deep Should a Paver Base Be? Gravel, Sand and the Mistakes That Sink Patios
Paver base depth: 4-6 inches of compacted gravel plus 1 inch of bedding sand (8-12 for driveways). Why to compact in thin lifts and what sinks patios.
2026-07-18
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Home & DIY · explainer
Rebar in a Concrete Slab: Spacing, Cover and Lap Splices Explained
Rebar spacing in a concrete slab: #4 bar at 12-18 in on centre, 3 in cover. How to count bars, why cover matters, and how lap splices differ from code.
2026-07-18
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Astronomy & Space · explainer
Telescope Magnification: Why the '600x' on the Box Is a Lie
Telescope magnification = focal length ÷ eyepiece focal length, but the useful limit is ~50× per inch of aperture, why aperture beats power.
2026-07-18
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Automotive · explainer
Why Your Tire Pressure Light Comes On in Winter (1 PSI per 10°F, Explained)
Tires lose about 1 PSI for every 10°F the temperature drops, so a cold snap can trigger your TPMS light with no leak, the physics and what to do.
2026-07-18
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Home & DIY · explainer
Roof Pitch Explained: 4/12 in Degrees, Walkability, and Minimum Slopes by Material
Roof pitch is rise per 12 of run, a 4/12 roof is 18.4°. The pitch-to-degrees chart, which roofs are walkable, and minimum slopes by material.
2026-07-17
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Productivity · explainer
What Is a Swimlane Diagram? Mapping Who Does What (and Where Work Stalls)
A swimlane diagram is a flowchart split into lanes, one per role, so every hand-off becomes a visible arrow. When to use one, lane counts, and lanes vs pools.
2026-07-17
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Charts & Design · explainer
Which Chart Type Should You Use? A Decision Guide (Bar, Line, Pie, Funnel, Radar, Waterfall)
Bar charts compare categories, line charts show change over time, pie charts show parts of a whole. Here's a decision framework for picking the right chart, plus when funnel, radar and waterfall charts beat all three, and the mistakes that make charts lie.
2026-07-17
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Calculators · explainer
How to Calculate Square Footage of a Room (Including L-Shapes and Odd Angles)
Square footage is length × width, a 12 × 10 ft room is 120 sq ft. How to handle L-shaped rooms, circles, triangles, flooring waste and square metres.
2026-07-14
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Home & DIY · explainer
What Is a Cord of Wood? Full Cord vs Face Cord (and How Not to Get Shorted)
A cord of wood is a 4 × 4 × 8 ft stack, exactly 128 cubic feet. A face cord is only one log deep, often just a third of that. How to spot a short cord.
2026-07-14
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Pets & Animals · explainer
How Much Chocolate Is Toxic to Dogs? (Type, Weight & Dose Explained)
How much chocolate is toxic to dogs depends on theobromine, the chocolate type and your dog's weight, the dose, vet risk thresholds, and what to do.
2026-07-13
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Network & IT · explainer
Mbps vs MB/s: Why Your Download Is 8× Slower Than Your Internet Plan
Mbps vs MB/s explained: a 100 Mbps plan downloads at about 12.5 MB/s because a byte is 8 bits, divide Mbps by 8 to get MB/s.
2026-07-13
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3D Printing · explainer
Why a Bigger 3D Print Uses So Much More Filament: The Cube Rule
The cube rule explains why scaling a 3D print to 200% uses 8× the filament, not 2×, plus why print time balloons and how to plan a resize.
2026-07-12
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Photography · explainer
How to Blur the Background: The 4 Keys to Depth of Field
Depth of field controls background blur, and four things set it: aperture, focal length, subject distance and sensor size. The recipe for a blurry background.
2026-07-12
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Pets & Animals · explainer
How Old Is My Dog in Human Years? The 7-Year Myth, Debunked
The 'multiply by 7' dog-age rule is a myth. Better methods: the 2020 epigenetic formula (16 × ln(age) + 31) and the size-based chart, with a worked example.
2026-07-12
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Physics · explainer
Elastic vs Inelastic Collisions: What's Conserved (and Why)
Momentum is conserved in every collision, but kinetic energy only in an elastic one. The difference, final-velocity formulas, and coefficient of restitution.
2026-07-12
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Weather & Atmosphere · explainer
Why 'Feels Like' Isn't the Temperature: Heat Index, Wind Chill and Wet-Bulb
Why 'feels like' isn't the temperature: humidity drives the heat index, wind drives the wind chill, and wet-bulb sets the survival limit of cooling.
2026-07-12
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Finance · explainer
Financial Ratios Explained: The 6 Families and How to Read Them
Financial ratios explained: the six families, liquidity, leverage, coverage, profitability, efficiency, valuation, with formulas, benchmarks and peer context.
2026-07-12
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Astronomy & Space · explainer
Golden Hour and Blue Hour: The Sun Angles That Make the Best Light
Golden hour isn't a clock time, it's a sun angle. The exact elevations that define golden hour, blue hour and the three twilights, and how to find them.
2026-07-12
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Travel & Trips · explainer
Why Flight Paths Curve on the Map: Great-Circle Distance
Great-circle distance is why flights arc north on a flat map, the shortest path over a round Earth. How it works and how the haversine formula computes it.
2026-07-12
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Solar & Energy · explainer
How Many Solar Panels Do I Need? A Simple Way to Size a System
How many solar panels you need depends on your energy use and your sun. The simple three-step sizing method, a worked example, and the margin to add.
2026-07-12
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Finance · explainer
How Much House Can You Afford? The 28/36 Rule Explained
How much house can you afford? The 28/36 rule checks two ratios against your income. How it works, how to turn it into a home-price ceiling.
2026-07-12
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Homebrewing · explainer
How to Calculate ABV: Original Gravity, Final Gravity and Alcohol
Calculate ABV from two hydrometer readings: ABV = (OG − FG) × 131.25. What original and final gravity mean, the formula, and when to use the accurate one.
2026-07-12
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Electronics & Circuits · explainer
How to Read SMD Resistor Codes (103, 4700, 01C and R47)
Decode SMD resistor codes: 3-digit, 4-digit, EIA-96 and R-notation markings, why 470 means 47 ohms, and the zero-ohm jumper.
2026-07-12
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Astronomy & Space · explainer
Why You Always See Space in the Past: Light Travel Time Explained
Light is fast but not instant, so you always see space in the past: the Sun 8 minutes ago, the nearest star 4 years back. How light travel time works.
2026-07-12
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Music & Audio · explainer
Why Every Octave Doubles: The Math Behind Musical Notes
Every musical note is a frequency: an octave doubles it and twelve equal semitones divide it. Why A = 440 Hz, what cents are, and equal temperament.
2026-07-12
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PDF Tools · explainer
How to Convert a PDF to JPG Without Uploading It
Convert PDF pages to JPG entirely in your browser, nothing uploaded, plus how to choose JPG vs PNG and the right resolution.
2026-07-12
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Privacy & Security · explainer
How to Redact Personal Data Before Pasting Text Into AI
Pasting text into ChatGPT can leak customer data. What counts as PII and how to strip it out locally in seconds before you hit send.
2026-07-12
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Electronics & Circuits · explainer
How to Read a Resistor Color Code (Bands to Ohms)
Resistor color code: the first two bands are digits, the next a ×10ⁿ multiplier, the last tolerance. Color values, which end to start from, and 4/5/6-band.
2026-07-12
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Biology & Lab · explainer
How to Predict Restriction Digest Fragment Sizes
Predict restriction digest fragment sizes from the sequence before you run the gel, how cut positions become bands and why topology changes the count.
2026-07-12
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Gardening & Plants · explainer
When to Start Seeds: Timing Your Whole Garden to the Last Frost
When to start seeds: count back from your average last spring frost, tomatoes ~7 weeks before, peas ~5, beans after. A crop-by-crop timing guide.
2026-07-12
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Mathematics · explainer
How to Solve a Triangle (Law of Sines & Law of Cosines)
Solve a triangle: how to pick between the law of sines and law of cosines for each case (SSS, SAS, ASA, AAS), and why SSA is the ambiguous one.
2026-07-12
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Statistics · explainer
The t-Test Explained: One-Sample, Two-Sample and Paired
A t-test tells you whether a difference in means is real or just chance. How the three types work, Welch vs pooled, and what the p-value really means.
2026-07-12
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Weather & Atmosphere · explainer
What Is VPD? Vapor Pressure Deficit Explained (with Target Ranges)
VPD (vapor pressure deficit) is the number growers tune instead of humidity because it includes temperature. What it means and target ranges by stage.
2026-07-12
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Chemistry & Lab · explainer
How to Find the pH of a Weak Acid (the ICE-Table Method)
A weak acid at 0.1 M isn't pH 1, it's closer to 3, because it barely ionizes. Here's why −log of the concentration fails, how to set up the ICE table, and how to solve for pH exactly instead of guessing that 'x is small'.
2026-07-12
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Chemistry & Lab · explainer
How to Balance Chemical Equations: The Algebra Method (Step by Step)
Balance any chemical equation with the algebra method: one unknown per species, one equation per element, solved for the smallest whole numbers.
2026-07-11
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Chemistry & Lab · explainer
Colligative Properties: Why Salt Melts Ice and Antifreeze Works
Colligative properties depend on how many particles dissolve, not what they are, freezing-point depression (ΔTf = i·Kf·m) and boiling-point elevation.
2026-07-11
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Color Tools · explainer
Accessible Color: Contrast Ratios and Color Blindness, Explained
Accessible color needs enough contrast (WCAG AA: 4.5:1 text, 3:1 large) plus cues beyond color, ~1 in 12 men are color-blind. How to get both right.
2026-07-11
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Color Tools · explainer
Extracting Colors from an Image: Pickers, Palettes and Naming
Extract colors from an image on-device: pick a pixel for exact HEX/RGB/HSL, pull a dominant palette with median-cut, and name the nearest CSS color.
2026-07-11
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Finance · explainer
Debt Snowball vs Avalanche: Which Pays Off Debt Faster?
Avalanche (highest rate first) pays the least interest; snowball (smallest balance first) gives faster wins. How each works and how to choose.
2026-07-11
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Home & DIY · explainer
How Much Do I Need? Estimating Paint, Tile, Concrete and Mulch
Estimating materials for any home project: area jobs (paint, tile) vs volume jobs (concrete, mulch), the formulas, coverage and waste allowances.
2026-07-11
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Cooking & Kitchen · explainer
Grams to Cups: Why a Cup of Flour Isn't a Cup of Sugar
A cup is volume, grams are weight, so each ingredient weighs differently: ~120 g flour, 198 g sugar, 336 g honey per cup. Why there's no single number.
2026-07-11
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Text Tools · explainer
Homoglyph Attacks: How Lookalike Characters Spoof Domains and Brands
Homoglyph attacks use confusable Unicode characters, like a Cyrillic а in “pаypal.com”, to spoof domains and brands. How they work and how to spot them.
2026-07-11
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Text Tools · explainer
Invisible Characters in Text: Zero-Width Spaces, Hidden Watermarks, and How to Remove Them
A zero-width space (U+200B) is invisible on screen but breaks search, code and CSV parsing, what the hidden characters are and how to detect and strip them.
2026-07-11
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Color Tools · explainer
OKLCH: The Modern CSS Color Format (and How to Convert from HEX)
OKLCH is a perceptually uniform CSS color format, oklch(L% C H), ~95% browser support and Tailwind 4's default. Why it beats HEX and HSL, and how to convert.
2026-07-11
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Chemistry & Lab · explainer
Oxidation Numbers: The Rules and How to Assign Them
Oxidation number rules in priority order, group 1 +1, oxygen −2, hydrogen +1, then solve the last element by balancing. Worked example: KMnO₄ → Mn +7.
2026-07-11
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Text Tools · explainer
Readability Scores Explained: Flesch Reading Ease, Grade Level, and How to Improve Them
Flesch Reading Ease scores text 0-100 (higher is easier); grade-level formulas give a US grade, what the scores mean and how to improve them.
2026-07-11
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Chemistry & Lab · explainer
How to Read the Periodic Table: Groups, Periods, Blocks and Trends
How to read the periodic table: groups share chemistry, periods count electron shells, blocks show which orbital fills, plus the key periodic trends.
2026-07-11
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Home & DIY · explainer
How Many Shingles Do I Need? Roofing Squares and Pitch Explained
How many shingles you need: multiply footprint by the slope factor, convert to roofing squares (100 sq ft each), then ~3 bundles per square.
2026-07-11
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Fitness & Exercise · explainer
The Runner's Math: Pace, Race Times and Heart-Rate Zones Explained
Runner's math in three formulas: pace = time ÷ distance, Riegel's race-time predictor, and heart-rate zones from your max HR, with worked examples.
2026-07-11
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Statistics · explainer
How Many People Do You Need to Survey? Sample Size Explained
The sample size for a proportion is n = z²·p(1−p) / E², at 95% confidence with a ±5% margin you need 385 responses, whatever your population size.
2026-07-11
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Physics · explainer
Series vs Parallel: Resistors and Capacitors (and Why They're Opposite)
Resistors in series add; in parallel their reciprocals add (total below the smallest). Capacitors do the exact reverse. The rules, the reason, a memory aid, and worked examples, so you never mix them up again.
2026-07-11
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Physics · explainer
The SUVAT Equations: Solve Any Constant-Acceleration Problem
The five SUVAT kinematic equations link displacement, velocity, acceleration and time. Know any three, find the other two, plus the equation-picking trick.
2026-07-11
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Chemistry & Lab · explainer
The Mole Explained: Converting Grams, Moles and Molecules
The mole links mass, moles and particles: moles = mass ÷ molar mass, particles = moles × 6.022×10²³. Convert grams, moles and molecules with worked examples.
2026-07-11
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Automotive · explainer
How to Read a Tire Size: 225/45R17 Decoded
How to read a tire size like 225/45R17: width (225), aspect ratio (45), radial (R) and rim diameter (17), and how to find the real overall diameter.
2026-07-11
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Generators · explainer
WiFi QR Codes: How They Work, the WIFI: Format, and How to Make One Safely
A WiFi QR code encodes the string WIFI:T:WPA;S:network;P:password;; how the format works, why special characters must be escaped, and how to make one safely.
2026-07-11
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Statistics · explainer
Z-Score to P-Value: How to Read the Normal Distribution
A p-value is the tail area of the normal curve beyond your z-score. z = 1.96 gives a two-tailed p of 0.05; z = 1.645 a one-tailed p of 0.05. How the conversion works, one- versus two-tailed, and why a table is coarser than the exact erf calculation.
2026-07-11
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Color Tools · explainer
Brand Colors: The Exact Hex Codes of Famous Brands, and How to Use Them Legally
Exact brand color hex codes, Netflix #e50914, Spotify #1db954, Tiffany #0abab5, for 1,100+ brands, plus when using a brand's palette is legal.
2026-07-10
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Network & IT · explainer
chmod 755 Explained: Unix File Permissions Without the Guesswork
chmod 755 explained: how the octal numbers work (read=4, write=2, execute=1), 644 vs 755, when to use 600, and why 777 is almost always wrong.
2026-07-10
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Network & IT · explainer
Cron Syntax Explained: The Five Fields, the Shortcuts, and the OR-Rule Trap
How cron expressions work, the five fields, special characters, and the day-of-month/day-of-week OR-rule that makes jobs run too often.
2026-07-10
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Biology & Lab · explainer
C1V1 = C2V2: How to Calculate Any Dilution (with Serial Dilutions)
The dilution equation C1V1 = C2V2 conserves solute, so V1 = C2V2/C1, to make 100 mL of 1× from a 10× stock, use 10 mL stock plus 90 mL diluent.
2026-07-10
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Biology & Lab · explainer
Hardy, Weinberg Equilibrium: Allele Frequencies, p²+2pq+q², and the χ² Test
Hardy, Weinberg predicts genotypes from allele frequencies (p²+2pq+q²=1). Find p and q from counts and test for equilibrium with a chi-square test.
2026-07-10
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Calculators · explainer
Markup vs Margin: Same Profit, Two Very Different Percentages
Markup vs margin: $60→$100 is a 66.7% markup but a 40% margin. Why markup is always bigger, how to convert, and the costly pricing mistake to avoid.
2026-07-10
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Calculators · explainer
Why Your First Mortgage Payment Is Almost All Interest
Mortgage amortization explained: why payment #1 on a $300k loan at 6% is $1,500 interest and just $299 principal, and how extra principal shortens the loan.
2026-07-10
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Photo Size Maker · reference
Passport Photo Size by Country: The Complete Guide (2026)
Most countries use the ICAO 35×45 mm photo and the US uses 2×2 inches, passport photo size, background and file rules worldwide, country by country.
2026-07-10
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Biology & Lab · explainer
Punnett Squares: Monohybrid, Dihybrid, and Where the 9:3:3:1 Comes From
Punnett squares explained: a monohybrid Aa × Aa cross gives a 3:1 phenotype ratio and a dihybrid AaBb × AaBb gives 9:3:3:1. How to fill the grid.
2026-07-10
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Biology & Lab · explainer
Reverse Complement of DNA: The Rule, the Steps, and Why Direction Matters
The reverse complement of ATGC is GCAT, complement each base (A↔T, G↔C), then reverse to read 5′→3′. How it differs from the complement.
2026-07-10
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Mathematics · explainer
Significant Figures: The Rules, the Ambiguous Cases, and How to Round Correctly
The four significant-figures rules explained digit by digit: which zeros count, why 1200 is ambiguous, and how to round to N sig figs (the 9.99 carry case).
2026-07-10
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Calculators · explainer
BMR vs TDEE: How Many Calories You Actually Need (and Why)
Your BMR is what you burn at rest; your TDEE is BMR times an activity factor, the real number that decides whether you lose, hold or gain. The Mifflin, St Jeor formula, the five activity multipliers, and how to set a deficit, worked through step by step.
2026-07-10
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Mathematics · explainer
0.1 + 0.2 ≠ 0.3: Why Most Calculators Quietly Round, and What Exact Arithmetic Looks Like
Every ordinary calculator uses floating point, which rounds past ~15 digits and turns 1/3 + 2/3 into 0.999…9. How exact arithmetic avoids all of it.
2026-07-09
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PDF Tools · explainer
PDF Accessibility After the EAA: What a Screen Reader Actually Needs From Your PDF
What makes a PDF accessible under the EAA, tags, language, title, text layer, alt text, which checks a machine can run, and how to triage it locally.
2026-07-08
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PDF Tools · explainer
Why PDF Redactions Keep Failing, and How to Redact (and Verify) for Real
PDF redaction fails when black boxes hide text instead of removing it. How redaction leaks, how to flatten pages for real, and the verification everyone skips.
2026-07-08
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File Converters · explainer
France's 2026 E-Invoicing Mandate: How to Open a Factur-X Invoice Without Accounting Software
From 1 September 2026 every French company must receive e-invoices, most as Factur-X hybrid PDFs. What it requires, the five profiles, how to read one.
2026-07-07
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Network & IT · explainer
IPv6 Crossed 50%: A Practical Subnetting Guide for the Dual-Stack Era
IPv6 subnetting made simple: why every LAN is a /64, how /48 and /56 allocations work, and the IPv4 habits to unlearn now that IPv6 is the majority.
2026-07-07
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File Converters · explainer
KSeF in 2026/2027: How to Open and Read an FA(3) Invoice XML, No Software, Nothing Uploaded
Poland's KSeF makes the FA(3) XML the binding invoice, mandatory since April 2026, penalties from 2027. What's inside it and how to read one.
2026-07-07
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Developer Tools · explainer
LLM Tokens Explained: What Your Prompts Actually Cost, and Why Claude & Gemini Counts Are Estimates
API bills are counted in tokens, not words. How tokenization works, the cost formula, why output tokens dominate, and why only OpenAI counts are exact.
2026-07-07
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Calendars · explainer
The 4-5-4 Retail Calendar Explained: Why Retailers Don't Use Normal Months
The NRF 4-5-4 calendar splits the retail year into 13-week quarters of 4-5-4 week months so retail sales compare like-for-like across years.
2026-07-06
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Calendars · explainer
Hijri, Hebrew, Persian and Julian: How the World's Calendars Actually Work
A guide to the world's major calendar systems, lunar, solar and lunisolar, how Hijri, Hebrew, Persian and Julian differ, and how to convert between them.
2026-07-06
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Codes & Ciphers · explainer
Morse, NATO, Binary and Classic Ciphers: Codes You Can Actually Read
Morse, NATO and binary are encodings anyone can reverse; Caesar, ROT13 and Vigenère are ciphers with a key. How they differ from real encryption.
2026-07-06
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File Converters · explainer
Received an Invoice as an XML File? XRechnung and ZUGFeRD Explained
XRechnung and ZUGFeRD explained: why Germany's mandate makes B2B invoices arrive as XML, the 2025-2028 timeline, and how to read one on-device.
2026-07-06
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Image Tools · explainer
Why iPhone Photos Won't Open on Windows, HEIC Explained (and How to Convert It)
HEIC to JPG: why iPhone photos won't open on Windows, Android or the web, and how to convert them privately in your browser (no upload).
2026-07-06
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Calendars · explainer
BS to AD (and Back): How the Nepali Bikram Sambat Calendar Works
Nepal's Bikram Sambat runs ~56 years 8 months ahead of AD, so 2024 AD is 2081 BS. Why BS months vary, and how to convert any date both ways.
2026-07-06
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PDF Tools · how-to
How to Password-Protect a PDF (or Remove a Password) Without Uploading It
PDF encryption uses AES, but online unlock tools want your document and its password together. How PDF passwords work and how to add or remove them locally.
2026-07-06
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Productivity · explainer
The Pomodoro Technique: Why 25-Minute Sprints Beat Marathon Focus
The Pomodoro Technique breaks work into 25-minute focus sprints with short breaks. Why it works, how to run it properly, and how to tune the intervals.
2026-07-06
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Productivity · explainer
Privacy-First Productivity: Plan, Focus and Track Without the Cloud
Privacy-first productivity tools that run in your browser and save to your device, Pomodoro, Eisenhower matrix, habit tracker, no account, no cloud.
2026-07-06
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Developer Tools · explainer
Base64 Is Not Encryption: What It Actually Does (and When to Use It)
Base64 re-spells bytes as 64 safe text characters so binary survives text channels, reversible by anyone, not encryption. The math, URL-safe variant, JWTs.
2026-07-05
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Text Tools · explainer
Character Limits Cheat Sheet: X/Twitter, SMS, Google, Instagram and More
X allows 280 characters, one SMS is 160, Google shows ~60 of a title and ~158 of a meta description, the full limits table plus the emoji trap.
2026-07-05
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Text Tools · how-to
How to Clean Up Any Messy List: Dedupe, Sort and Fix Broken Text in 4 Steps
Clean up any messy list in four steps: fix line breaks, dedupe, natural-sort, and pattern-fix with find & replace, each step one click.
2026-07-05
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Size Converters · explainer
Women's Clothing Size Conversion: US, UK, EU, IT Charts, and Why Vanity Sizing Broke Them
A US 8 is a UK 12, EU 38, FR 40, IT 44 and JP 13. Get the full conversion chart, the fixed offsets behind it, and why a 1975 size 12 became today's size 6.
2026-07-05
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Color Tools · explainer
HEX, RGB, HSL and CMYK: CSS Color Formats Explained (With Conversion Math)
HEX, RGB and HSL are one color in three dialects, how each CSS format works, when to use which, the conversion math, and why CMYK never quite matches.
2026-07-05
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File Converters · how-to
CSV to JSON Without the Traps: Quotes, Commas, Semicolons and Typed Values
CSV to JSON fails in predictable ways: quoted commas, semicolon Excel exports, numbers arriving as strings. How the conversion works, with fixes for each trap.
2026-07-05
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Privacy & Security · explainer
What Your Photos Reveal: EXIF, GPS Location and How to Strip Them
EXIF metadata in phone photos includes camera, timestamps and GPS coordinates accurate to a few meters. What leaks, and how to strip it in your browser.
2026-07-05
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Size Converters · explainer
Hat Sizes Decoded: Why 7⅛ Means Your Head's Diameter (Charts + Measuring Guide)
Fitted hat size = head circumference in inches ÷ π. Measure your head, then convert 52-64 cm to US, UK fitted and S, XXL letter sizes.
2026-07-05
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Image Tools · explainer
JPEG vs PNG vs WebP: Which Image Format to Use (and How to Shrink Files 90%)
JPEG vs PNG vs WebP: JPEG for photos, PNG for screenshots and transparency, WebP for 25-35% smaller web files, plus the resize-then-compress workflow.
2026-07-05
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File Converters · explainer
JSON vs YAML vs XML: Which Data Format for Which Job
APIs speak JSON, humans edit YAML, legacy systems demand XML. How the three formats differ, when each wins, and how to convert without losing data.
2026-07-05
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Size Converters · how-to
Kids' Shoe Sizes by Age: US, UK, EU Charts, and the 13C-to-1Y Mystery
Kids' shoe sizes run 2C-13.5C then restart at 1Y (which is bigger). Full US/UK/EU chart with ages and cm, measuring method, and growing-room rules.
2026-07-05
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PDF Tools · how-to
How to Merge, Split and Rotate PDFs Without Uploading Them Anywhere
Merge, split and rotate PDFs in your browser, nothing uploaded. How local, lossless PDF editing works, and the four most common fixes step by step.
2026-07-05
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Text Tools · explainer
camelCase vs snake_case vs kebab-case: Which Naming Case Goes Where
camelCase for JavaScript, snake_case for Python, kebab-case for URLs and CSS, PascalCase for classes, the full naming-case map and converter.
2026-07-05
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Generators · explainer
How Strong Is a Password, Really? Entropy Explained (Length Beats Complexity)
Password entropy = length × log₂(alphabet size). Why a 16-char lowercase password beats an 8-char symbol soup, and what NIST actually recommends.
2026-07-05
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Date & Time · explainer
Unix Timestamps Explained: Seconds vs Milliseconds, UTC and the Year 2038
A Unix timestamp counts seconds since 1 January 1970 UTC. Convert to a date, tell seconds from milliseconds (10 vs 13 digits), and the Year 2038 bug.
2026-07-05
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Audio & Video · explainer
WAV vs MP3: Lossless, Lossy, and Why Converting MP3 to WAV Doesn't Improve Anything
WAV stores every sample (~10 MB per stereo minute); MP3 discards what you won't hear at a tenth the size. Why MP3→WAV can't restore quality.
2026-07-05
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Color Tools · explainer
WCAG Color Contrast Explained: The 4.5:1 Rule Without the Jargon
WCAG AA requires 4.5:1 contrast for normal text, 3:1 for large text and UI. What the ratio means, how to check it, and how to fix failing brand colors.
2026-07-05
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Size Converters · explainer
Bra Size Conversion and Sister Sizes: US, UK and EU Explained
Bra size conversion across US, UK, EU and FR, plus how sister sizes fix a bra that almost fits, and how to measure band and cup at home.
2026-07-04
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Unit Converters · how-to
Celsius to Fahrenheit: Formula, Charts for Weather, Fever and Ovens
Celsius to Fahrenheit: °F = °C × 9/5 + 32. The exact formula, a mental shortcut, and charts for weather, fever, ovens and Kelvin.
2026-07-04
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Unit Converters · how-to
Cups to mL and Grams: The Baking Conversion Guide That Actually Works
1 US cup = 236.59 mL, but an Australian cup is 250 mL and a Japanese cup 200 mL. The cup-systems table, cups-to-grams for baking, and why weighing wins.
2026-07-04
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Calculators · explainer
How EMI Is Calculated: The Exact Formula Banks Use (With Worked Examples)
EMI = P·r·(1+r)ⁿ ÷ ((1+r)ⁿ−1). See it worked step by step: why early EMIs are mostly interest, the flat-rate trap, and how tenure drives total interest.
2026-07-04
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Unit Converters · how-to
Kg to Lbs Conversion: Formula, Charts and the 2-Second Mental Trick
1 kg = 2.2046 lbs exactly. The full kg to lbs guide: formula, mental trick, charts for body weight, luggage, gym plates and newborns.
2026-07-04
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Unit Converters · explainer
MB vs GB Explained: Why a 1 TB Drive Shows Only 931 GB
MB vs GB explained: 1 GB = 1,000 MB by the decimal standard, but Windows counts in binary, which is why a 1 TB drive shows only 931 GB.
2026-07-04
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Calculators · how-to
How to Calculate Percentages: All 3 Forms, Fast Tricks and Real Examples
How to calculate percentages: every problem is one of three forms. The formulas, the X% of Y = Y% of X swap trick, reverse percentages, and common mistakes.
2026-07-04
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Size Converters · how-to
How to Measure Your Ring Size at Home (US, UK, EU Charts Included)
Measure your ring size at home with a paper strip: circumference in mm is your EU size, and US 7 = UK N = EU 54.4. Full US/UK/EU conversion chart.
2026-07-04
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Unit Converters · explainer
How Many Miles Is a 5K, 10K, Half and Full Marathon? (+ Pace Charts)
A 5K is 3.11 miles, a 10K 6.21, a half 13.11 and a marathon 26.22 miles (42.195 km). Pace charts, treadmill conversions and the 26.2-mile backstory.
2026-07-04
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Size Converters · explainer
Shoe Size Conversion: US, UK, EU and cm, and Why Brands Never Quite Agree
A US men's 9 is a UK 8, EU 42.5 and 26.5 cm, usually. The men's and women's charts, the barleycorn history, and the foot-measuring method that wins.
2026-07-04