FitCalc
Body composition

Body fat calculator

Estimate your body-fat percentage with the U.S. Navy method. Enter your height and a few tape measurements, and see your body-fat percent, category, and fat and lean mass.


Body fat estimateLive
17.5%Fitness
Fat mass32.4 lb
Lean mass152.6 lb

U.S. Navy circumference method. It is a solid estimate, not a lab measurement like a DEXA scan, so use it to track change over time.

How it works

How the Navy method estimates body fat

The U.S. Navy method estimates body fat from the ratio of your circumference measurements to your height. Because fat tends to sit at the waist and hips, those girths, set against your neck and height, predict body-fat percentage surprisingly well without calipers or a scan.

It is an estimate, so the real value is in tracking it. Measure the same way each time and watch the trend rather than fixating on a single reading. Add your weight and the calculator splits it into fat mass and lean mass.

Questions

Body fat questions

How does this body fat calculator work?
It uses the U.S. Navy circumference method: a formula that estimates body-fat percentage from your height and a few tape measurements (neck and waist, plus hips for women). No special equipment needed, just a tape measure.
How accurate is the Navy method?
For most people it lands within a few points of a DEXA or hydrostatic reading, which is good for a tape measurement. It is best used to track change over time, since consistent measuring matters more than one absolute number.
How do I measure correctly?
Measure relaxed, without pulling the tape tight. Neck just below the larynx, waist at the navel for men and the narrowest point for women, and hips at the widest point. Take each measurement twice and average.
What is a healthy body-fat percentage?
It differs by sex. Roughly, fitness range is about 14 to 17 percent for men and 21 to 24 percent for women, with athletes lower. The calculator labels your result so you can see where it falls.
Do you save my results?
No. Everything is calculated in your browser and nothing is stored or sent anywhere.