Body Fat Calculator (U.S. Navy Method)
A tape measure and a minute — your estimated body fat percentage.
Estimates for education — not medical advice. Talk to a healthcare professional about what is healthy for you.
How to estimate your body fat
- Grab a soft tape measure. Take your height, neck, and waist (add hips if female), following the measuring tips beside the tool.
- Pick your units and sex, then enter the measurements.
- Press Calculate body fat. Your percentage appears with its category.
- Track the trend, not one number. Measure the same way monthly — the Navy method is best at showing change over time.
Frequently asked questions
How do you calculate body fat percentage at home?
The most practical at-home method is the U.S. Navy tape method: measure your height, neck, and waist (plus hips for women) with a soft tape, and the formula estimates your body fat percentage. This calculator runs that formula for you.
What is the U.S. Navy body fat method?
A tape-measure method the U.S. Navy developed to estimate body composition. Men use height, neck, and waist; women add hips. The formulas use base-10 logarithms of the measurements, all converted to centimeters.
What is a healthy body fat percentage?
Commonly cited healthy bands: men 14–24%, women 21–31%. Athletes sit lower (men 6–13%, women 14–20%), while 25%+ for men and 32%+ for women is in the obese range.
How accurate is the Navy body fat method?
Typically within about 3–4 percentage points of DEXA scans for most people — decent for tracking change over time. Consistent measuring (same spots, same tension, morning) matters more than any single reading.
Is this medical advice?
No. These are estimates for education only — not medical advice. Talk to a healthcare professional about what is healthy for you.
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U.S. Navy tape-method body fat percentage and category.
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