🔁 Image Format Converter
PNG ↔ JPEG ↔ WebP in one click, locally — with the transparency and quality trade-offs made visible instead of silently mangled.
How the image format converter works
The browser decodes the source and re-encodes it in the target format with its native codec. The conversions differ in what they can carry: PNG is lossless and keeps transparency; JPEG is lossy and has no alpha channel — transparent regions get flattened onto a background; WebP does both lossy compression and transparency. The tool warns when a conversion drops something the source had.
The classic mistake this tool prevents: converting a transparent logo to JPEG and getting a white (or black) box behind it. If you need transparency, the answer is PNG or WebP — no JPEG setting fixes it, because the format simply has no alpha channel.
Frequently asked questions
Which format should I convert to?
Photos → JPEG (universal) or WebP (smaller); screenshots, diagrams, text → PNG; anything needing transparency → PNG or WebP. Converting a photo to PNG makes it dramatically larger for zero visible gain.
What happens to transparency when converting to JPEG?
JPEG has no alpha channel, so transparent pixels must be flattened onto a solid background (white by default here). If the result looks wrong, the source needed WebP or PNG instead.
Does converting JPEG to PNG improve quality?
No — JPEG's compression loss already happened and is baked into the pixels. PNG conversion just stores those same pixels losslessly in a much bigger file. Converting the other way (PNG → JPEG) does discard detail; do it once, from the original.
Can I convert HEIC photos from an iPhone?
Only if your browser can decode HEIC, which most currently can't (Safari can). If the picker accepts the file and a preview appears, the conversion works; otherwise export as JPEG from the Photos app first.
Are my images uploaded?
No — decoding and re-encoding happen with the browser's built-in codecs, on your device, offline-capable.
Related image tools
From the blog
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Why iPhone Photos Won't Open on Windows — HEIC Explained (and How to Convert It)
iPhones save photos as HEIC — half the size of JPEG, but unreadable on Windows, Android and the web. What HEIC is, why it breaks things, how to convert it privately, and how to make your iPhone shoot JPEG instead.
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JPEG vs PNG vs WebP: Which Image Format to Use (and How to Shrink Files 90%)
JPEG for photos, PNG for screenshots and transparency, WebP for the web at 25–35% smaller. How each format works, the conversion mistakes that ruin images, and the resize-then-compress workflow that cuts files by 90%.