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, exact on sequences of any length, processed entirely on your device.
- 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, with the method used shown, so you know which formula applies.
- 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, or find the mass to weigh out for a target molarity.
- 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, for a linear fragment or a circular plasmid.
- 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, monohybrid, dihybrid or trihybrid.
- 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, from the initial size, growth rate and time.
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.