How does the US Navy body fat method work?

It estimates body fat from the circumference of the neck, waist, and, for women, the hips, along with height. It is a quick tape measure method that correlates reasonably well with more accurate tests, though it is an estimate, not a medical measurement.

What is a healthy body fat percentage?

General fitness ranges are often quoted as roughly 14 to 24% for men and 21 to 31% for women, with athletes lower. Healthy ranges vary by age and individual, so treat the result as a guide and talk to a health professional for advice.

How should I measure for accuracy?

Use a flexible tape, measure relaxed, and take each measurement at the same point a couple of times. Measure the waist at the navel, the neck below the larynx, and for women the hips at the widest point.

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.

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Sex

Height (cm)

Neck (cm)

Waist (cm)

estimated body fat

Category--

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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BMI Calculator: body mass index.
Ideal Weight Calculator: healthy weight range.
Calorie Calculator: daily calories.
TDEE Calculator: energy expenditure.

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