Navy Body Fat Calculator – Estimate Your Body Fat Percentage
The Navy Body Fat Calculator uses the US Navy circumference method to estimate your body fat percentage based on simple body measurements. Developed for military fitness assessments, this formula provides a reliable and non-invasive way to gauge body composition for both men and women. Simply enter your height, neck, waist, and (for women) hip measurements to get your results instantly.
Enter your height in centimeters.
Measure around the narrowest part of your neck.
For men: measure at the navel. For women: measure at the narrowest point.
Women only: measure at the widest part of your hips.
Your results will appear here
How to Use This Calculator
1. Select your gender using the radio buttons at the top of the calculator. 2. Enter your height in centimeters. 3. Measure the circumference of your neck at its narrowest point and enter the value. 4. Measure your waist circumference — men should measure at the navel, while women should measure at the narrowest point. 5. Women must also enter their hip circumference measured at the widest point. 6. Click Calculate to see your body fat percentage, estimated fat mass, lean mass, and body fat category.
How the US Navy Body Fat Method Works
The US Navy body fat calculation method was developed to provide a quick, field-usable estimate of body fat percentage without expensive equipment. It relies on circumference measurements and height, using logarithmic formulas derived from population studies.
Formula for Men
For males, the formula is:
- Body Fat % = 495 / (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450
All measurements are in centimeters. The waist is measured at the navel level.
Formula for Women
For females, the hip measurement is added because women naturally carry more fat in the hip and thigh region:
- Body Fat % = 495 / (1.29579 − 0.35004 × log10(waist + hip − neck) + 0.22100 × log10(height)) − 450
Body Fat Categories
Body fat percentage is interpreted differently for men and women:
- Men: Essential Fat <6%, Athletes 6–13%, Fitness 14–17%, Average 18–24%, Obese ≥25%
- Women: Essential Fat <14%, Athletes 14–20%, Fitness 21–24%, Average 25–31%, Obese ≥32%
Limitations
While the Navy method is practical and widely used, it is an estimation. Results can vary based on measurement accuracy, body type, and ethnicity. For clinical assessments, methods such as DEXA scans or hydrostatic weighing provide higher precision.