Free calculators for QC and QA laboratories. Each tool shows its working step by step, so you can check it against your worksheet. Each page also explains the formula, gives worked examples and lists the typical pharmacopoeial or regulatory acceptance criteria. They are learning and checking aids: always follow your approved methods and SOPs.
Assay CalculatorHPLC/UV assay as % of label claim or % w/w, with standard RSD check and step-by-step working.Open calculator →RSD CalculatorMean, SD and %RSD (n − 1) with a pass/fail check against your system suitability limit.Open calculator →Weight Variation CalculatorUniformity of mass for 20 tablets or capsules against Ph. Eur. 2.9.5 / BP / IP limits.Open calculator →Control Chart Calculator (I-MR)Control limits, Nelson-rule signals, Cpk and Ppk for APQR and process trending.Open calculator →Sample Size CalculatorSurvey or proportion, estimating a mean, and WHO √N + 1 container sampling plans.Open calculator →Molarity & Molality CalculatorMolarity, mass to weigh, molality and C₁V₁ = C₂V₂ dilutions for reagents and buffers.Open calculator →Density & Specific Gravity CalculatorPycnometer specific gravity and density in g/mL at 20 or 25 °C.Open calculator →Measurement Uncertainty CalculatorGUM uncertainty budget for pH and HPLC assay: combined and expanded uncertainty, conformity check and CSV export.Open calculator →