Body Fat Calculator
Estimate your body fat percentage from simple measurements (height, neck, waist and — for women — hip).
What is Body Fat?
Body fat percentage is the proportion of your body weight that is fat tissue. Healthy ranges differ by sex and age; athletes typically run 6–13% (men) or 14–20% (women).
How is it calculated?
The U.S. Navy circumference formula approximates body fat from height and circumference measurements (in inches):
- Men: 86.010·log10(waist−neck) − 70.041·log10(height) + 36.76
- Women: 163.205·log10(waist+hip−neck) − 97.684·log10(height) − 78.387
Frequently Asked Questions
- How accurate is the Navy formula?
- Within ±3% of more advanced methods like DEXA when measurements are taken correctly.
- Where do I measure waist?
- Men: at the navel. Women: at the smallest point above the navel.