body fat calculator
U.S. Navy method — metric & imperial — fitness category — no sign-up.
Measure just below the larynx (Adam's apple), perpendicular to neck axis.
Men: measure at the navel. Women: measure at the narrowest point.
Body fat percentage is a screening tool, not a medical diagnosis. The Navy method is an estimate with ±3–4% accuracy. Consult a healthcare provider for a complete assessment.
Body fat categories — men
| 2 – 5% | Essential fat |
| 6 – 13% | Athlete |
| 14 – 17% | Fitness |
| 18 – 24% | Acceptable |
| 25%+ | Obese |
Body fat categories — women
| 10 – 13% | Essential fat |
| 14 – 20% | Athlete |
| 21 – 24% | Fitness |
| 25 – 31% | Acceptable |
| 32%+ | Obese |
What is the Navy method?
Developed by the U.S. Navy, this formula estimates body fat from circumference measurements and height. It's more accurate than BMI-based methods because it accounts for body shape, not just weight.
How to measure
Use a flexible tape measure. Measure at the same time each day. Keep the tape parallel to the floor and snug but not compressing the skin.
FAQ
How accurate is this?
The Navy method has ±3–4% accuracy vs. DEXA scans (the gold standard). It's a reliable estimate for most people, but not suitable for clinical diagnosis.
Why do women need hip measurements?
Women naturally store more fat in the hip and thigh region. The Navy formula accounts for this with a separate hip measurement.
Is my data stored?
No — everything runs in browser. No uploads or saved data.