CalcMates builds free, practical calculators for the industries that measure things for a living — agriculture, mining, construction, livestock, and water & environment. Every tool is designed to give you a trustworthy number quickly, on a phone in the field or at a desk.
How we build our calculators
Each calculator is built from a documented formula. We show that formula, the units involved, and a worked example with real numbers on every page, so you can see exactly how the result is reached and check it against your own figures. Where a result depends on standards, regulations or material properties, we state those assumptions and cite our sources.
Our commitment to accuracy
A calculator is only useful if it's right. We verify every formula against a worked example before it's published, show you the formula and the units on the page, and date every tool so you know how current it is. The maths is correct — your results depend on the quality of the inputs you provide.
How we keep it free
The calculators and their guides are free and always will be. The site is supported by advertising. If you spot an error or want a calculator we don't have yet, we'd like to hear about it.