About CheckedCalc

CheckedCalc is a set of free engineering calculators for design engineers in the UK and the US. Each tool is built to be checked, not just used.

What every calculator includes

Item	Why
Cited standard or reference	You can trace every formula to its source.
Stated assumptions	You know where the method stops being valid.
Worked example	You can reproduce a known result before trusting a new one.
SI units first, inches on request	One unit system per calculation, converted only at input and output.
Downloadable report	Inputs, method and results in one printable record.

Who writes it

The calculators are written by The CheckedCalc editor. See the author page and the editorial policy.