Free Body Fat Calculator
Estimate your body fat percentage with nothing but a tape measure. This calculator uses the U.S. Navy circumference method — height, neck, waist (and hip for women) — to produce an instant, equipment-free estimate with a fitness category.
How to Use the Body Fat Calculator
- Enter your gender and measurement units.
- Measure height, neck and waist (plus hip for women) with a tape.
- Click Calculate Body Fat for your Navy-method estimate.
Features
Implements the official U.S. Navy formulas for men and women, accepts centimeters or inches, validates measurements for common mistakes, and classifies your result from essential fat through athlete, fitness, average and obese ranges.
Benefits & Use Cases
Track fat-loss progress more meaningfully than the scale alone, since weight can stay flat while body composition improves. It is also a handy pre-check before investing in calipers or a DEXA scan.
Tips
Measure the waist at the navel while relaxed — do not suck in. Take measurements in the morning and use the same tape position each time for comparable trends.
Frequently Asked Questions
How accurate is the Navy method?
Typically within 3–4% of DEXA scans for most people — good for tracking trends, though not lab-grade.
Why do women need a hip measurement?
The Navy formula for women accounts for typical fat distribution, so hip circumference improves the estimate.
What is a healthy body fat percentage?
Roughly 10–20% for men and 18–28% for women is considered a healthy fitness range; athletes tend to be lower.
Can I use inches instead of centimeters?
Yes — just switch the unit selector and enter all measurements in inches.
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