Biology & Lab Tools
Exact, deterministic biology tools — from reverse-complementing a sequence to filling a Punnett square or planning a serial dilution. Everything is computed in your browser, so your sequence and data are never uploaded — and the answers are byte-exact where a chatbot would drift.
🧫 Molecular biology & lab bench
- DNA Reverse Complement & Translate Reverse-complement, transcribe (DNA→mRNA) and translate any DNA or RNA sequence
- Dilution Calculator (C1V1=C2V2) Solve the dilution equation C₁V₁ = C₂V₂ for any missing value, plan a serial dilution tube-by-tube, or compute a dilution factor.
- GC Content & Melting Temperature (Tm) Get the GC content and melting temperature (Tm) of a DNA sequence or primer
- DNA / RNA Molecular Weight & ng↔pmol Get the molecular weight of a DNA or RNA sequence, convert between ng, pmol and molecule copies, and read concentration from an A260 measurement.
- Cell Doubling Time Calculator Find the doubling time, specific growth rate (µ) and number of generations from two cell counts or OD readings taken over a time interval.
- Molarity Calculator Work out the molarity of a solution from mass, molar mass and volume
- OD600 to Cell Density Calculator Estimate cell density (cells/mL) from an OD₆₀₀ reading, using a conversion factor you can set for your organism.
- Protein Molecular Weight Calculator Get the molecular weight of a protein in daltons and kilodaltons straight from its amino-acid sequence, with the residue composition.
- Hemocytometer Cell Counting Calculator Turn a hemocytometer count into cells per mL and a total cell number, accounting for your dilution (e.g. trypan blue) and suspension volume.
- Michaelis–Menten Enzyme Kinetics Calculator Find the reaction velocity v for an enzyme from Vmax, Km and the substrate concentration [S], using the Michaelis–Menten equation.
- qPCR Efficiency Calculator Convert the slope of a qPCR standard curve into amplification efficiency, and see the fold change per cycle.
- Restriction Enzyme Digest Calculator Pick your enzymes and paste a DNA sequence to find every recognition site, the cut positions and the resulting fragment sizes
- Protein Isoelectric Point (pI) & Net Charge Paste a protein sequence to get its isoelectric point (pI), the net charge at pH 7, and a titration curve showing charge across the whole pH range.
🧬 Genetics & population
- Punnett Square Calculator Cross two parent genotypes and get the full Punnett square with genotype and phenotype ratios
- Hardy–Weinberg Equilibrium Calculator Find allele frequencies (p and q), the expected Hardy–Weinberg genotype proportions, and a χ² test of whether a population is in equilibrium.
- Population Growth Calculator Project a population under exponential growth, or logistic growth with a carrying capacity
Lab bench math, kept on your bench
Molecular biology runs on small, repetitive calculations: reverse-complementing and translating a DNA sequence, planning a C₁V₁=C₂V₂ dilution or serial dilution, working a Punnett square or Hardy–Weinberg equilibrium, and finding GC content, melting temperature or molecular weight. These tools do each precisely, and — importantly for unpublished sequences — process everything in your browser, so a sequence you paste is never uploaded.
That local processing means you can work with proprietary or pre-publication data safely, and the tools keep working offline. For general lab math see Chemistry & Lab and Statistics.
Frequently asked questions
Are these biology calculators accurate?
Yes — every tool uses exact, deterministic formulas (the genetic code, C₁V₁=C₂V₂, p²+2pq+q², nucleotide masses). There are no approximations or lookup tables that could drift, and the sequence and genetics tools are byte-exact where a chatbot would make mistakes.
Is my sequence or data uploaded?
No. Everything runs in your browser with JavaScript — sequences, counts and results never leave your device. That matters for unpublished or proprietary sequence data, which should not be pasted into a chatbot or an upload site.
Why build biology tools that an AI could answer?
Because AI chatbots reliably get these wrong: they drift on long reverse-complements, mis-fill Punnett grids, and miscalculate χ² tests. A deterministic tool gives the exact answer every time, with the working shown.
Do these work for coursework and the lab?
Both. The genetics tools (Punnett, Hardy–Weinberg) suit AP-Biology and undergraduate work, while the bench tools (dilution, molarity, Tm, doubling time) are everyday lab calculations for students and researchers alike.