How to use this hub
Pick your lab task first: qPCR, cell culture, genetics, or ecology.
Follow the quick path for your task, then open one tool at a time.
Use the sections below when you need a full catalog.
Quick paths
qPCR path: A260 concentration & purity, DNA/RNA converter, qPCR standard curve, then ΔCt / ΔΔCt.
Cell culture path: Hemocytometer then Cell seeding.
Microbiology path: Start with CFU/mL.
Genetics path: Punnett square, Mendelian chi-square, Hardy–Weinberg, then Wright–Fisher.
Ecology path: Growth curve, Diversity index, then Wright–Fisher.
Order is a guide. Adjust to your workflow.
Featured
- Hardy–Weinberg equilibrium and chi-square calculator.
Check Hardy–Weinberg equilibrium from genotype counts or allele frequencies, and compute the chi-square statistic.
- ΔCt / ΔΔCt calculator (relative expression).
Paste qPCR Ct values to calculate ΔCt/ΔΔCt, log2FC, and fold change.
Lab practice
- Hemocytometer calculator (cells/mL & viability)
Calculate cell concentration (cells/mL) and viability (%) from hemocytometer counts and dilution. Supports improved Neubauer (10^4 factor), examples, warnings, copy, CSV/LaTeX, and share URLs.
- CFU/mL calculator (dilution, plated volume)
Calculate CFU/mL from dilution, plated volume, and colony counts. Supports 30–300 guide range, per-dilution summary, plots, CSV/LaTeX, and share URLs.
- DNA/RNA converter (ng/µL ↔ nM ↔ copies)
Convert DNA/RNA length and type into ng/µL, nM, and copies/µL. Includes total amount from volume, copy, CSV/LaTeX, and share URLs.
- NGS coverage calculator (average depth)
Estimate average coverage from target size and reads or total Gb. Adjust usable/mapping/on-target/duplicate rates, back-calculate required reads, and show ≥k× fraction (Poisson).
- NGS library concentration (ng/µL → nM)
Convert ng/µL and fragment length to nM, then plan dilution and pooling (equal volume/equal molar). Supports table input, examples, copy, CSV/JSON, and share URLs.
- Cell seeding calculator
Back-calculate required cell suspension and media volume from target cells/well or cells/cm². Includes per-well volume, overage, viability correction, copy, CSV/LaTeX, and share URLs.
- ELISA standard curve fitter (4PL/5PL)
Fit 4PL/5PL to standard points and estimate unknown concentrations. Includes weighting, residuals, back-calculation (recovery), share URLs, and CSV/JSON output.
Molecular biology
- A260 concentration & purity calculator
Calculate DNA/RNA concentration and purity ratios from A260/A280/A230 with dilution. Includes total amount, optional blank correction, copy, CSV/LaTeX, and share URLs.
- Primer Tm calculator
Calculate primer Tm and annealing temperature guides from DNA sequences with nearest-neighbor or simple formulas.
- PCR master mix calculator
Compute master mix volumes from reaction count/volume and stock/final concentrations. Supports overage, 96/384 wells, protocol text, CSV/JSON, and share URLs.
- Ligation molar ratio calculator
Calculate insert amounts from vector mass/size and molar ratio presets. Includes copy, CSV/JSON, and share URLs.
- DNA assembly mix calculator (Gibson / Golden Gate)
Calculate backbone/insert amounts and reaction volumes for assembly workflows. Includes examples, table input, copy, CSV/JSON, and share URLs.
Biochemistry
- Michaelis–Menten fitter (Km & Vmax)
Fit Michaelis–Menten to substrate concentration and initial rate, with scatter + fit curve, residuals, copy, CSV/LaTeX, and share URLs.
Genetics
- Punnett square generator (mono/di-hybrid)
Generate Punnett squares from parent genotypes and show genotype ratios and phenotype ratios. Includes Markdown table copy, CSV/LaTeX, and share URLs.
- Mendelian chi-square test calculator
Calculate χ², df, and p-value from observed counts and expected ratios (3:1, 9:3:3:1). Shows expected counts, contributions, charts, CSV/LaTeX, and share URLs.
Ecology & evolution
Suggested order: Growth curve → Doubling time → Logistic K (upper limit)
- Growth curve fitter (exponential & logistic)
Fit exponential and logistic growth to time-series data to estimate r, doubling time, and K. Includes residuals, model comparison, CSV/LaTeX, and share URLs.
- Diversity index calculator (Shannon & Simpson)
Compute Shannon and Simpson indices from category counts. Shows ln/log2/log10, D/1−D/1/D, Hill numbers, evenness, examples, copy, CSV/JSON, and share URLs.
- Wright–Fisher genetic drift simulator
Simulate genetic drift with N, p0, generations, and replicates. Visualize trajectories and fixation/extinction rates, with selection/mutation/migration options.
All biology tools
- A260 Calculator (DNA/RNA Concentration & Purity).
Use A260/A280/A230 and dilution to estimate DNA/RNA concentration (ng/µL) plus A260/280 and A260/230 purity ratios.
- Beta diversity calculator (Jaccard / Bray–Curtis).
Compute beta diversity between samples using Jaccard (presence/absence) or Bray–Curtis (abundance).
- Cell seeding calculator | cells/well → required volume.
Calculate required cell suspension and media volume from target cells/well (or cells/cm²), number of wells, volume.
- Centrifuge converter (rpm ↔ RCF ×g) | by rotor radius.
Convert between centrifuge speed (rpm) and relative centrifugal force (RCF, ×g) using rotor radius (mm/cm/in).
- CFU/mL calculator (dilution, plated volume).
Calculate CFU/mL from dilution, plated volume, and colony counts.
- Diversity index calculator (Shannon & Simpson).
Calculate diversity indices from category counts.
- DNA assembly mix calculator (Gibson/Golden Gate).
Plan Gibson or Golden Gate assembly mixes from backbone and insert sizes, ratios, and concentrations.
- DNA/RNA converter (ng/µL ↔ nM ↔ copies).
Convert between mass concentration (ng/µL), molar concentration (nM), and copy number (copies/µL) from DNA/RNA.
- ELISA standard curve fitter (4PL/5PL).
Fit 4PL/5PL curves to ELISA standards, estimate unknown concentrations, and review weighting, residuals.
- Genetic drift simulator (Wright–Fisher) | allele.
Simulate genetic drift with the Wright–Fisher model.
- Growth curve fitter (exponential & logistic).
Fit exponential and logistic growth to time-series data and estimate growth rate r, doubling time, and carrying.
- Hardy-Weinberg equilibrium calc (expected frequency/χ²).
From the observed AA/Aa/aa, allele frequency (p,q), expected frequency (p²,2pq,q²), χ² and p value are.
- Hemocytometer calculator (cells/mL & viability).
Calculate cell concentration (cells/mL) and viability (%) from hemocytometer counts and dilution.
- IC50/EC50 calculator (4PL/5PL curve fit) | Dose–response.
Paste concentration–response data and estimate IC50/EC50 (the 50% point) with 4PL/5PL curve fitting.
- Kd calculator | Binding curve fit (one site / Hill).
Fit binding data with one-site or Hill models to estimate Kd.
- Ligation molar ratio calculator | Vector:insert amounts.
Calculate required insert mass (ng) and volume (µL) from vector mass, length, and desired molar ratio (e.g., 1:3).
- Mendelian ratio chi-square test calculator.
From observed counts and expected ratios (3:1, 9:3:3:1, etc.), calculate χ², df, and p-value.
- Michaelis–Menten fitter (Km, Vmax) | nonlinear fit.
Estimate Km and Vmax by nonlinear fitting of the Michaelis–Menten equation from substrate [S] and initial rate v.
- MOI calculator (multiplicity of infection).
Calculate MOI from cell count, viral titer, and inoculum volume, then solve required volume or titer for a target.
- NGS coverage calculator (average depth).
Estimate average NGS coverage depth.
- NGS library concentration (ng/µL → nM) | dilution.
Convert NGS library concentration from ng/µL and fragment length to nM, then calculate normalization dilutions.
- PCR master mix calculator | reactions, concentrations.
Calculate PCR/qPCR master mix volumes from reaction volume/count and stock/final concentrations.
- PCR Primer Tm Calculator | annealing temperature guide.
Calculate primer melting temperature (Tm) from DNA sequences and estimate PCR annealing temperature (Ta).
- Protein standard curve calculator (BCA / Bradford).
Build a protein assay standard curve for BCA or Bradford data, fit linear or quadratic models, and estimate unknown.
- Punnett square generator (1- and 2-gene).
Generate a Punnett square from parent genotypes (AA/Aa/aa, AaBb, etc.) and summarize genotype proportions (%/ratio).
- qPCR standard curve calculator.
Build a qPCR standard curve from Quantity and Ct, calculate slope, intercept, R², and PCR efficiency (%).
How to use this page effectively
This page works as a practical learning entry point. Use the sections and linked resources as a workflow: confirm your objective, check assumptions, and follow one branch at a time.
How it works
Start by reading the main explanation area, then identify your first decision point. Compare one scenario against a baseline, keep all other inputs steady, and record assumptions as part of your result note.
When to use
Use this page when you need quick context before detailed calculations or when choosing the next page in the same domain.
Common mistakes to avoid
- Scanning many links at once and losing track of what was changed.
- Comparing outputs without recording input assumptions.
- Assuming one page can answer all constraints in a workflow.
- Skipping fallback checks like units, date convention, and default values.
Worked example
Set a baseline, then test one alternative at a time. If direction and scale are both reasonable, keep the branch. If not, move backward and validate where the assumption changed.
See also
FAQ
What should I define first on this page?
Start with a clear baseline scenario and minimum required inputs. Keep optional controls at defaults for the first run, then change one assumption at a time.
Why do identical values differ across pages or tools?
Different pages often use different defaults, units, period definitions, and rounding rules. Align these before comparing outputs.
How do I avoid misleading conclusions from this calculator?
Use one baseline, one assumption change, and one interpretation rule. If direction and scale are both reasonable, the result is usually robust enough for planning.
Can I trust the values for operational decisions?
These pages are useful for planning and learning, but for regulated, legal, or high-value decisions, validate assumptions and methods with official guidance or a qualified reviewer.
Is my input uploaded to a server when I run this page?
Core calculations are performed in your browser. Sharing is explicit and controlled by you; no hidden upload is required to compute an outcome.
How to use Biology calculators effectively
Page intent
This page is a practical help page: it should guide readers from intent to action. Begin with the goal, provide a clear method, then show what changes matter most. Clarity of intent is the most important SEO signal for user retention.
Decision framing
Frame every recommendation with boundaries. What is fixed, what is adjustable, and what is not considered should be explicit. Users who understand constraints trust the result more than users who only see a single number.
Practical workflow
A reliable workflow is: define target, run baseline, try one alternative, compare difference in one dimension only, and only then relax another assumption. This keeps causality visible and reduces explanation risk.
Typical mistakes
Do not treat calculated output as certainty, do not mix assumptions across iterations, and do not skip sanity checks. A small misunderstanding in a base value can create large errors in final interpretation.