Estimated fat mass
34.9 lb
Tape-measure body composition estimate
Free Body Fat Calculator
A body fat calculator estimates the percentage of your body weight made up of fat. This free tool uses height and simple circumference measurements to estimate body fat, fat mass, and lean mass for adults.
Circumference estimate
Enter your measurements
Use a flexible tape and measure on bare skin without compressing it.
Estimated body fat
19.4%
General range
Category labels are broad adult reference bands, not clinical diagnoses or fitness standards.
Estimated lean mass
145.1 lb
How to use this result: repeat measurements under similar conditions and focus on the trend. Hydration, tape placement, and the equation itself can change the estimate.
Educational estimate for adults. It does not diagnose health or replace a clinician, DEXA scan, Bod Pod, or another validated body composition assessment.
How to measure for a consistent estimate
Keep the tape level
Use a flexible tape on bare skin. Keep it horizontal and snug without compressing the skin.
Measure after exhaling
Stand relaxed and take waist or abdomen measurements at the end of a normal exhale.
Repeat the same way
Take two or three readings and track trends under similar hydration and time-of-day conditions.
Measurement landmarks follow the U.S. Navy body composition assessment training guide. This consumer tool is not an official military assessment.
Body fat calculator FAQ
What is a body fat calculator?
A body fat calculator estimates the percentage of body weight made up of fat. This calculator uses height and tape-measured circumferences rather than BMI alone.
How accurate is the U.S. Navy body fat formula?
It is a practical screening estimate, not a direct measurement. Tape placement, hydration, body shape, and the equation can all affect the result.
Where should I measure my waist?
For the male equation, measure the abdomen at navel level after a normal exhale. For the female equation, measure the narrowest natural waist and the widest part of the hips.
Is body fat percentage the same as BMI?
No. BMI compares weight with height, while body fat percentage estimates how much of total weight is fat. Each is a screening estimate with different limitations.
How often should I measure body fat?
For trend tracking, measure every two to four weeks under similar conditions. Small day-to-day changes are more likely measurement noise than real body-composition change.
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