Calculate your body fat percentage using the US Navy method. Enter your neck, waist, and hip measurements for accurate results. Includes body fat categories for men and women.
16.9%
Body Fat Percentage
Fitness
Category
Body Fat
Body fat percentage is the ratio of fat tissue to total body weight. Unlike BMI, it provides a true picture of body composition — you can have a normal BMI but high body fat (known as "skinny fat"), or a high BMI due to muscle mass. Understanding your body fat percentage helps you set realistic fitness goals and monitor actual progress.
Healthy ranges are 6–24% for men and 14–31% for women. Excessively low body fat (below 5% for men, 12% for women) is dangerous to health. High body fat significantly increases risk of type 2 diabetes, cardiovascular disease, and hypertension.
US Navy Method
This calculator uses the US Navy method, developed for assessing military personnel body composition. The method uses body circumference measurements and height in a logarithmic formula that provides clinically acceptable accuracy without expensive equipment.
For men: BF% = 495 / (1.0324 − 0.19077 × log10(waist − neck) + 0.15456 × log10(height)) − 450
For women: BF% = 495 / (1.29579 − 0.35004 × log10(waist + hip − neck) + 0.22100 × log10(height)) − 450
Accuracy is typically within 3–4% when measurements are taken correctly. Measure in the morning, before eating.
Measurement
Neck: Measure below the larynx, slightly tilted downward. Do not flex your neck muscles.
Waist (men): At the level of the navel, during normal breathing — do not suck in your stomach.
Waist (women): At the narrowest point of the waist.
Hip (women): At the widest point of the hips and buttocks.
Categories
Essential fat (Men: <6%, Women: <14%)
Minimum amount necessary for life. Dangerously low.
Athletic (Men: 6–13%, Women: 14–20%)
Typical for athletes and people with intensive training.
Fitness (Men: 14–17%, Women: 21–24%)
Good physical shape, visible muscle definition.
Average (Men: 18–24%, Women: 25–31%)
Healthy range for average adults.
Obese (Men: >25%, Women: >32%)
Elevated health risk. Consider consulting a healthcare provider.
Measurement methods
Skinfold calipers, DEXA scan, and bioelectrical impedance each have different accuracy levels. Use the same method consistently.
The US Navy method estimates body fat percentage using body circumference measurements (neck, waist, and hips for women) along with height. It uses a logarithmic formula developed for military fitness assessment and is accurate to within 3–4% when measurements are taken correctly.
Healthy ranges differ by gender: men 6–24%, women 14–31%. Athletes typically fall in the 6–13% (men) or 14–20% (women) range. Essential fat — the minimum needed for life — is below 5% for men and 12% for women.
Men: measure at the level of the navel during normal breathing. Women: measure at the narrowest point of the waist. Do not suck in your stomach. Take the measurement in the morning for consistency.
BMI uses only height and weight, so it cannot distinguish between fat and muscle. Body fat percentage directly measures the proportion of fat tissue in your body, making it a more accurate indicator of health risks and fitness level.
A combination of caloric deficit (eating less than your TDEE), strength training to preserve muscle mass, and cardiovascular exercise is most effective. Losing 0.5–1% body fat per month is a realistic and sustainable rate.