Estimate your body fat percentage using body measurements with the U.S. Navy method.
Select your gender, then enter your waist circumference, neck circumference, and (for women) hip circumference in centimeters.
Click "Calculate" to see your estimated body fat percentage and the corresponding fitness category.
Measure at the widest points: waist at the navel, neck at the narrowest point, and hips at the widest point.
This calculator uses the U.S. Navy body fat formula:
Men: Body Fat % = 495 / (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450
Women: Body Fat % = 495 / (1.29579 − 0.35004 × log10(waist + hip − neck) + 0.22100 × log10(height)) − 450
Example: A male with waist 85 cm, neck 38 cm, height 178 cm.
The Navy method has a typical error margin of about 3-4% compared to hydrostatic weighing. It is considered one of the more reliable tape-measure methods for estimating body fat.
For men: essential fat 2-5%, athletes 6-13%, fitness 14-17%, acceptable 18-24%, obese 25%+. For women: essential fat 10-13%, athletes 14-20%, fitness 21-24%, acceptable 25-31%, obese 32%+.
Women tend to store more fat around the hips. The Navy formula accounts for this gender difference by including hip circumference in the female calculation to improve accuracy.
Measure first thing in the morning before eating or drinking, and use a flexible tape measure. Keep the tape snug but not compressing the skin, and measure each site two or three times for consistency.