Body Fat Calculator
Estimate body fat percentage with the US Navy circumference method using height, neck, waist (and hip for women). Everything runs in your browser. For reference only.
Enter your measurements
FAQ
How accurate is a tape measure method?
The US Navy formula is typically within ±3–4 percentage points. Good for tracking trends; use BIA or DEXA for precision.
How do I take the measurements?
Neck just below the larynx; waist at the navel (men) or narrowest point (women); hips at the widest point. Keep the tape snug but not compressing.
What are the categories based on?
ACE categories: for men, <6% essential, 6–13% athlete, 14–17% fitness, 18–24% average, 25%+ obese; women's thresholds run ~8 points higher.
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