Calculator index
Verified calculators, not black boxes.
Use practical calculators with visible formulas, engineering assumptions, limitations, and citations.
Fluids & Piping
Pipe flow, pressure loss, pump head, Reynolds number, and flow-unit tools.
Pipe Reynolds NumberScreen circular pipe flow regime from average velocity, inside diameter, and viscosity.Pipe Velocity From Flow RateCalculate average velocity in a full circular pipe from volumetric flow rate and inside diameter.Darcy-Weisbach Pressure LossCalculate straight-pipe major pressure loss and head loss from a user-supplied Darcy friction factor.Pump Head From PressureConvert a pump pressure rise or differential pressure into equivalent liquid head.Volumetric Flow ConversionConvert common SI, U.S. liquid, and cubic-foot-per-minute volumetric flow units.
Engineering Statistics & Sample Size
Confidence intervals and sample-size planning for engineering tests.
Sample Size For Estimating A MeanEstimate the number of independent measurements needed to bound a continuous mean by a target margin of error.Sample Size For Estimating A ProportionEstimate the number of binary observations needed to bound a proportion or nonconformance rate by a target margin of error.Confidence Interval For A MeanCompute a one-sample confidence interval for a continuous mean from summary statistics.Confidence Interval For A ProportionCompute a Wilson score confidence interval for a binary proportion or nonconformance rate.