💪 Body Fat Calculator
Estimate your body fat percentage using the US Navy circumference method — no special equipment needed.
Your Measurements (cm or inches)
Body Fat Percentage
0%
Category
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Fat Mass
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Lean Mass
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Fat to Lose (to fit)
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US Navy Body Fat Formula
The US Navy method estimates body fat from circumference measurements. It's reasonably accurate (±3–4%) and requires only a tape measure.
Men: %BF = 86.010 × log₁₀(waist − neck) − 70.041 × log₁₀(height) + 36.76
Women: %BF = 163.205 × log₁₀(waist + hip − neck) − 97.684 × log₁₀(height) − 78.387
(all measurements in inches)
Women: %BF = 163.205 × log₁₀(waist + hip − neck) − 97.684 × log₁₀(height) − 78.387
(all measurements in inches)
Body Fat Percentage Categories
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2–5% | 10–13% |
| Athletic | 6–13% | 14–20% |
| Fit | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Obese | 25%+ | 32%+ |
Where should I measure my waist? +
Measure your waist circumference at the narrowest point, usually at the navel level or halfway between your lowest rib and hip bone. Keep the tape parallel to the floor and breathe normally — don't suck in your stomach.
How accurate is this method? +
The Navy method has a margin of error of approximately ±3–4% compared to DEXA (the gold standard). It's most accurate for average-build individuals and less accurate for very muscular or very obese people. DEXA, hydrostatic weighing, or air displacement plethysmography are more precise.