About this tool
Enter your sex, height and weight in metric or imperial units to estimate your lean body mass with the Boer formula and the resulting fat mass and body-fat percentage. It all runs locally in your browser.
Frequently asked questions
What is the Boer formula?
It estimates lean body mass from height and weight with sex-specific coefficients. Fat mass is then your total weight minus the lean mass.
Is this the same as a body-fat scale?
No — it is a formula-based estimate from height and weight only, so it cannot match a direct body-composition measurement, but it gives a useful ballpark.