Validation work you can defend in an audit
Free calculators for the arithmetic a small QC lab does every day, and a guided validation suite that ends in an auditor-ready report.
No account, nothing to install · Statistics certified against NIST reference datasets
Linearity study
ICH Q2(R2) acceptance criteria
- r²
- 0.9994
- Slope
- 0.02111
- Standards
- 5
12free calculators
100%test coverage on the engine
0intermediate values rounded
The calculators
Every calculator runs the same engine: intermediate values are never rounded, results are shown to a significant-figure count you choose, and full precision is what the copy button gives you. The regression and descriptive statistics are certified against the NIST Statistical Reference Datasets.
- Mean, SD and %RSDReplicate precision with a confidence interval on the mean
- Calibration curveLinear regression, residual plot, back-calculated unknowns
- LOD and LOQEvery σ your data supports, side by side, per ICH Q2(R2)
- Spike recovery% recovery corrected for dilution, and accuracy studies
- MolarityMass, concentration or volume, with MW looked up for you
- DilutionC₁V₁ = C₂V₂, plus a serial dilution planner
- Solution prepDilute a concentrated acid from its density and assay %
- Percent concentrationw/v, w/w and v/v, and the conversions between them
- ppm / ppbThe parts-per ladder, with density stated rather than assumed
- Molecular weightMolar mass, elemental composition, hydrate vs anhydrous
- Dry basisLoss on drying, and results moved between bases
- Buffer preparationHenderson–Hasselbalch with pKa at your working temperature
All twelve are on the calculators page. Free, no account, nothing to install.
Method validation and verification
The calculators are a free sample of a larger tool: guided ICH Q2(R2), USP <1225> and AOAC validation workflows that carry a study from its protocol to an auditor-ready report — the statistics underneath it are the ones already running on these pages. The suite is live, with four study sections sharing one study record and one audit trail.
Ready to run your own study?
Sign in free, start a guided study, and finish with an auditor-ready report — built on the same statistics as the calculators above.