Estimate your body fat percentage with a tape measure. This free body fat calculator uses the US Navy method to give your body fat %, a category, and your fat and lean mass — a quick estimate, not a target.
Measurements
cm
cm
cm
cm
kg
Measure relaxed, in a straight line: waist at the navel, neck below the larynx, hip at the widest point. The US Navy method estimates body fat from these.
Estimated body fat
— %
Enter your measurements
Category
—
Fat mass
—
Lean mass
—
Method
US Navy
An estimate — circumference methods have a margin of error and can’t replace tools like DEXA. Healthy ranges vary by individual; use this as a rough guide, not a target.
Use this free body fat calculator to estimate your body fat percentage from simple tape measurements. Enter your height, neck and waist (plus hip for women) to get an estimate using the US Navy method.
What this body fat calculator shows you
A body fat calculator estimates the percentage of your weight that’s fat, using body measurements rather than scales alone. This one uses the US Navy circumference method and shows your estimated body fat percentage, a category, and — if you add your weight — your fat mass and lean mass.
How the US Navy method works
It uses the relationship between your height and the circumference of your neck and waist (and hips for women) to estimate body fat. It’s quick and needs only a tape measure, though like all simple methods it has a margin of error.
Body fat percentage categories
Category
Men
Women
Essential fat
2–5%
10–13%
Athletic
6–13%
14–20%
Fitness
14–17%
21–24%
Average
18–24%
25–31%
Above average
25%+
32%+
Women naturally carry more essential fat than men. These ranges are general references, not personal targets.
How to measure accurately
Waist: around the navel, relaxed, not sucked in.
Neck: just below the larynx, tape sloping slightly down at the front.
Hip (women): around the widest part.
Keep the tape level and snug but not tight, and measure twice.
Why body fat % is more useful than weight alone
Two people of the same weight can look and feel very different depending on how much is muscle versus fat. Body fat percentage adds context that the scale and even BMI can miss — though for accuracy, methods like DEXA scans are the gold standard.
Body Fat FAQ
How do I calculate body fat percentage?
This calculator uses the US Navy method, which estimates body fat from your height and the circumference of your neck and waist (plus hips for women). Enter the measurements and it returns an estimated percentage.
What is a healthy body fat percentage?
General reference ranges put "fitness" at roughly 14–17% for men and 21–24% for women, with "average" a little higher. Women naturally carry more essential fat. Healthy ranges vary by individual.
How accurate is the US Navy body fat method?
It's a reasonable estimate from simple measurements, but it has a margin of error and depends on measuring carefully. Methods like DEXA scans or hydrostatic weighing are far more precise.
How should I measure my waist and neck?
Measure relaxed: the waist around the navel without sucking in, and the neck just below the larynx. Keep the tape level and snug but not tight, and measure twice for consistency.
Is body fat percentage better than BMI?
They measure different things. BMI uses only height and weight, while body fat percentage estimates how much of your weight is fat. Body fat % can give extra context, especially for muscular people, but both are estimates.
Is the body fat calculator free to use?
Yes, this body fat calculator is completely free, needs no sign-up, and gives instant results in your browser.
