Body Fat Calculator
Estimate your body fat percentage, fat mass and lean mass from a few tape-measure readings, using the US Navy circumference method.
Not medical advice. This body fat calculator gives an estimate only, using the US Navy circumference method, it is not medical advice and is less accurate for very lean or very muscular people. For a precise measurement, ask your GP about a DEXA scan or other clinical body composition test.
Enter your measurements
Your estimated body fat percentage and category appear here as you type.
How body fat percentage is calculated
This calculator uses the US Navy circumference method, developed by the Naval Health Research Center as a quick, equipment-free way to estimate body fat from height and a few tape-measure readings. For men, it uses waist and neck measurements; for women, it also uses hip measurement. The formula is a logarithmic regression fitted against underwater-weighing (hydrostatic) results, so it's reasonably accurate for most body types but can be less reliable for very lean or very muscular people. If you enter your weight, we also estimate your fat mass and lean (fat-free) mass in kilograms.
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