Body Fat Calculator
Estimate your body fat percentage
Calculator
Measure below larynx
At navel level
How to Use
Estimate your body fat percentage
Select gender
Choose male or female for accurate formula
Enter measurements
Input neck, waist, and hip (women) circumferences
Enter height
Input your height in cm or feet/inches
View results
See body fat percentage and category
Navy Body Fat Formula (Men)
BF% = 86.010 × log10(waist - neck) - 70.041 × log10(height) + 36.76
For women: BF% = 163.205 × log10(waist + hip - neck) - 97.684 × log10(height) - 78.387
Frequently Asked Questions
For men: Essential fat 2-5%, Athletes 6-13%, Fitness 14-17%, Average 18-24%, Obese 25%+. For women: Essential 10-13%, Athletes 14-20%, Fitness 21-24%, Average 25-31%, Obese 32%+. Women naturally carry more essential fat.
Navy method (using measurements) is accurate within 3-4%. Calipers: 3-5% error. Bioelectrical impedance (scales): 3-8% error depending on hydration. DEXA scans are most accurate (1-2% error) but expensive. Track trends over absolute numbers.
Use the Navy method: measure neck and waist circumference (plus hips for women) at the narrowest/widest points. Take measurements first thing in the morning after using the bathroom. Be consistent with measurement location and timing.
BMI uses only height and weight, ignoring muscle vs fat composition. A muscular athlete might have high BMI but low body fat. Body fat percentage directly measures fat mass vs lean mass, making it more useful for fitness assessment.