Body Fat Calculator
Estimate your body fat percentage using the US Navy circumference method. Measure your neck and waist (and hips if you are female), enter your height, and get an instant estimate plus where it falls on the standard body fat scale.
How to use the body fat calculator
- Pick your unit, select your sex, and enter your height.
- Measure your neck and waist with a tape (women also measure the hips) and enter them.
- Read your estimated body fat percentage and its category.
Examples
Average-build man
Male, height 180 cm, neck 38 cm, waist 85 cm
About 16.1% body fat (Fitness range)
Woman with hip measurement
Female, height 165 cm, neck 32 cm, waist 75 cm, hip 95 cm
About 27.4% body fat (Average range)
Frequently asked questions
What is the US Navy body fat method?
It is a formula developed by the Naval Health Research Center that estimates body fat from a few tape measurements. Men use neck and waist; women add the hips. It needs no special equipment.
How do I take the measurements correctly?
Use a flexible tape held snug but not tight. Measure the neck below the larynx, the waist at the navel, and (for women) the hips at the widest point. Stand relaxed and do not pull the tape in.
How accurate is it compared to calipers or a DEXA scan?
It is a rough estimate. Studies put it within a few percentage points for most people, but skinfold calipers and especially DEXA scans are more precise. Use it to track trends over time rather than as an exact figure.
What do the body fat categories mean?
Common bands for men are essential fat (2 to 5 percent), athletes (6 to 13), fitness (14 to 17), average (18 to 24) and obese (25 and up). For women each band sits roughly eight points higher because women carry more essential fat.
Why does the women's formula need a hip measurement?
Women store more fat around the hips, so the Navy formula adds the hip circumference to better reflect total body fat. That is why a hip value is required for a female estimate.
Is my data sent anywhere?
No. The calculation runs entirely in your browser. Your measurements never leave your device.
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