Body Fat Calculator
This calculator estimates your body fat percentage using the US Navy tape measure method, a quick way to gauge body composition without special equipment like skinfold callipers or a DEXA scan. You start by choosing your sex, since the formula and the healthy ranges differ for men and women, then enter your height along with your neck and waist measurements in centimetres; women also enter a hip measurement, because the female formula factors in waist plus hip minus neck rather than waist minus neck alone. The calculator instantly returns your estimated body fat percentage and places it into a category, from essential fat through athletic, fitness, average, and above average, so you can see roughly where you sit against general fitness benchmarks. For a reliable result, measure with a flexible tape held snug but not tight: the neck just below the larynx, the waist at the navel, and for women the hips at their widest point, taking each measurement a couple of times to check consistency. Because the method relies on a handful of circumference readings rather than a clinical scan, it works best for tracking changes in your own body over time rather than as a precise one-off figure. Treat the result as an indicative estimate only, not a medical or diagnostic measurement, and see a health professional if you want a more accurate assessment of your body composition.
An estimate using the US Navy method. For an accurate assessment, see a health professional.
How it works
The US Navy method uses the difference between the waist and neck for men, and waist plus hip minus neck for women, together with height, in a logarithmic formula. It is a quick estimate from a tape measure, not a clinical body composition test.
Measuring tips
Measure the neck just below the voice box, the waist at the navel, and for women the hips at the widest point. Keep the tape level and snug but not tight, and measure relaxed.
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