Calculator Body
Body fat calculator
Estimate your body fat percentage with nothing but a tape measure, using the U.S. Navy circumference method. It runs on your device — measurements go nowhere.
Estimated body fat
0%
The Navy method is an estimate — roughly ±3–4% versus a DEXA scan. Use it to track a trend, not as an exact figure.
By the numbers Context
What your body-fat percentage means
Body-fat percentage answers a question BMI cannot: how much of your weight is actually fat, versus muscle, bone, and water. Two people at the same BMI can have very different body compositions, which is why body fat is often the better health signal — especially for people who train. A certain amount of fat is essential; the goal is a healthy range, not the lowest possible number.
The U.S. Navy circumference method used here estimates body fat from your height and a couple of tape measurements. It is popular because it needs no special equipment and is reasonably reliable for tracking change over time. It will not match a lab scan exactly — expect it to be within a few percentage points — so it is most useful for watching the trend rather than fixating on a single reading.
10–20%
a typical fitness-to-average body-fat range for men
ACE
18–28%
a typical fitness-to-average range for women
ACE
±3–4%
how close the Navy tape method tends to land versus a DEXA scan
Research
Sources: American Council on Exercise (ACE) body-composition categories; U.S. Navy circumference method validation studies.
Frequently asked questions
How is body fat calculated with a tape measure?
The U.S. Navy method uses your height plus neck and waist measurements (and hips for women) in a formula that estimates body-fat percentage. This calculator does the maths once you enter the measurements.
What is a healthy body fat percentage?
It differs by sex. For men, roughly 6–13% is athletic, 14–17% fit, and 18–24% average. For women, roughly 14–20% is athletic, 21–24% fit, and 25–31% average. Some fat is essential — around 3% for men and 10–12% for women.
Is the Navy body fat method accurate?
It is a reasonable estimate — usually within about 3–4 percentage points of a DEXA scan — and very good for tracking change over time. For a precise one-off figure, a DEXA or Bod Pod is more accurate.
What is the difference between BMI and body fat?
BMI is just weight relative to height and cannot tell muscle from fat. Body-fat percentage measures composition directly, so it gives a truer picture of health for muscular or very lean people.