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Lab calculators, built for the bench.

Fast, accurate calculators for solution prep, molecular biology, and analytical chemistry — from dilutions to calibration curves. Free forever, no friction.

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Calculators

Dilution Calculator

C₁V₁ = C₂V₂ and serial dilutions

Solve for any unknown in a simple dilution. Run serial dilutions with a custom factor and see all intermediate concentrations.

  • Simple dilution — solve any variable
  • Serial dilution table
  • Full unit conversion (mM, µM, nM…)

General Calculations

Conversions and bench formulas

Convert temperature, pressure, mass, and volume, plus run Beer-Lambert, RPM/RCF, and Henderson-Hasselbalch calculations.

  • Temperature, pressure, mass, and volume
  • Beer-Lambert absorbance
  • RPM/RCF and buffer ratio calculators

Molecular Weight

Formula parser and molar mass

Calculate molar mass from chemical formulas like NaCl, glucose, CaCl₂·2H₂O, and CuSO₄·5H₂O with element breakdowns.

  • Parentheses and hydrate support
  • Element mass contribution table
  • Send molar mass to reagent prep

PCR Master Mix

PCR, qPCR (TaqMan, SYBR), Q5

Plan PCR or qPCR master mixes with adjustable excess factor, concentration- or fixed-volume components, and pipette accuracy warnings.

  • PCR, qPCR (TaqMan, SYBR), Q5 presets
  • 10% excess by default
  • Pipette-volume sanity check

Stock Solution Planner

C₁V₁ = C₂V₂ working dilutions

Mix a working solution from a stock. Calculates stock volume, diluent volume, and bench-ready instructions with pipette-accuracy warnings.

  • Molar and mass-based units
  • Pipette-accuracy warnings
  • Bench prep sheet

Lab Label Generator

Reagent labels and Pro batch sheets

Create printable labels for reagents, freezer stocks, aliquots, buffers, and media with storage, expiration, lot, and prepared-by fields.

  • Free single-label export
  • Tube, cryovial, and bottle layouts
  • Pro batch label sheets

Calibration Curve

Linear regression and R²

Fit a least-squares line to your standards, read off the equation, R², and standard error, then interpolate an unknown sample concentration from its signal.

  • Editable standards table (paste from a sheet)
  • Equation, R², and standard error
  • Scatter plot with fitted line

LOD / LOQ

Detection and quantitation limits

Calculate the limit of detection and limit of quantitation from a calibration curve (LOD = 3.3σ/S, LOQ = 10σ/S) or from replicate blank measurements, following ICH Q2.

  • Calibration-curve or blank-replicate methods
  • Residual or intercept σ
  • Configurable LOD/LOQ factors

QC Statistics

%RSD, recovery, and outliers

Summarize replicate precision (mean, SD, %RSD, confidence interval), test for an outlier with Grubbs’ test, and check spike recovery and percent error for method QC.

  • Mean, SD, %RSD, and confidence interval
  • Grubbs' single-outlier test
  • Spike recovery and percent error

Reagent Prep

Solutions, buffers, and recipes

Calculate how much solute to weigh for a target concentration and volume. Supports molarity, % w/v, % v/v, and common buffer presets.

  • Molarity, % w/v, % v/v modes
  • PBS, TAE, TE, TBE buffer presets
  • Prep sheet instructions

Why scientists choose LabTools

Designed for real bench work, not demos.

No friction

Open a calculator and start computing immediately. No account, no ads, no paywalls for core features.

Scientifically precise

Unit-aware calculations across the full range — nM to M, µL to L, mg/mL to % w/v.

Built for the bench

Large touch targets, clear result display, and mobile-first layout for tablet and phone use at the bench.

Ready to calculate?

No account needed. Just open a tool and go.