The US Navy method is a reasonable estimate for most people, usually within a few percent of more expensive methods, and is very consistent for tracking progress.

Should I compare measurements over time?

Yes. Measure under similar conditions and at the same body locations. The trend is usually more useful than treating one estimate as an exact body-fat reading.

Health & Fitness

Body Fat Calculator

Estimate your body fat percentage using the US Navy circumference method.

Free browser toolRuns in your browserNo sign-up

Sex

Height (cm)Neck (cm)Waist (cm)

16.9%

Body fat · Fitness

Uses the US Navy circumference method. Measure the neck below the larynx, the waist at the navel, and (for women) the hips at the widest point.

This tool is for general information only and is not medical advice. Talk to a qualified healthcare professional before making health decisions.

About the Body Fat Calculator

This calculator estimates your body fat percentage using the US Navy circumference method, which needs only a tape measure and no special equipment.

Enter your height and a few body measurements and it returns an estimated body fat percentage along with a fitness category. It is a practical way to track changes over time.

Measurements are calculated in your browser and never uploaded. Circumference methods are estimates and can differ from lab measurements.

Key features

US Navy tape-measure method
Body fat percentage and category
Separate formulas for men and women
Private, in-browser calculation

How to use

1Select your sex and enter your height.
2Measure and enter your neck, waist and (for women) hips.
3Read your estimated body fat percentage.

Examples

US Navy estimate

Input: Male, 175 cm tall, 38 cm neck, 85 cm waist

Output: Estimated body-fat percentage and category

Small changes in tape placement affect the estimate, so repeat measurements consistently.

Frequently asked questions

How do I measure correctly?: Measure the neck just below the larynx, the waist at the navel, and (for women) the hips at the widest point. Keep the tape level and snug but not tight.
How accurate is it?: The US Navy method is a reasonable estimate for most people, usually within a few percent of more expensive methods, and is very consistent for tracking progress.
Should I compare measurements over time?: Yes. Measure under similar conditions and at the same body locations. The trend is usually more useful than treating one estimate as an exact body-fat reading.

Open a related tool to prepare your files or refine the finished result.