Body Fat Calculator

It uses the US Navy circumference method. For men: 495 / (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450. For women, the inner term uses log10(waist + hip − neck) with different coefficients.

It is a population-fit equation that lands within a few percentage points of skin-fold methods for most people, but it can drift for very athletic builds, short stature, or atypical body shape. Treat it as an estimate, not a measurement.

If waist is not larger than neck (men) or waist plus hip not larger than neck (women), the log10 inputs are non-positive and the formula has no meaningful output. The calculator shows a dash in that case.