Body Fat Calculator
The U.S. Navy circumference method estimates body-fat percentage from height, neck, and waist. Hip is included only when Sex is Female.
How to use
- Set Sex to Male or Female. Hip (cm) stays hidden for Male and appears only for Female.
- Enter Height (cm), Neck (cm), and Waist (cm). For Female, also enter Hip (cm). If hip is missing, the result says Enter hip. If height, neck, or waist is missing, it says Enter measurements.
- Click Calculate. The result is a body-fat percent. The line under it says the figure is an estimate and that categories vary by age and sex.
When it helps
Use a tape percent when you can repeat the same neck and waist spots and you want a number that is not only the scale. The BMI calculator needs weight and height only, so the two screens answer different questions and can disagree.
The ideal weight calculator returns kilograms from height and sex, not a fat percent. Keep that result separate from the percent on this page. Neither tool merges the two into one score.
Limits
That percent is an estimate from a tape formula, not a clinical diagnosis. It is not a DEXA scan. The detail line says categories vary by age and sex, but this page does not apply an age table and does not print a fitness label.
Male math uses waist minus neck, together with height. Female math uses waist plus hip minus neck, together with height. If the waist is not larger than the neck, or waist plus hip is not larger than the neck, the percent is not usable. The form also does not name tape landmarks, so the number follows wherever you placed the tape.
Questions
Why is Hip missing?
Hip (cm) is shown only after Sex is Female. Male uses height, neck, and waist only.
Does the result say athletic or high?
No. You get a percent. There is no age-and-sex category lookup on this page.
Is this a substitute for a scan?
No. A DEXA scan is a different method. This page is circumference math only, and the percent should be read as an estimate.