Body Fat Percentage Calculator (US Navy Method)
Enter your measurements to estimate body fat percentage. For best accuracy, measure with a soft tape while relaxed and standing upright.
What is body fat percentage?
Body fat percentage is the proportion of your total body weight that comes from fat tissue. Unlike body weight alone, it gives you a clearer picture of body composition by separating fat mass from lean mass (muscle, bone, organs, and water). Two people can weigh the same but have very different body fat percentages, health profiles, and fitness levels.
How this BF percentage calculator works
This calculator uses the U.S. Navy circumference formula, a widely used method that estimates body fat from simple tape measurements. It does not require calipers or expensive scanning equipment, making it practical for home use.
Measurements used
- Men: Height, neck circumference, and waist circumference
- Women: Height, neck circumference, waist circumference, and hip circumference
The formula is most reliable when measurements are taken consistently: same tape, same time of day, and similar hydration status.
Body fat percentage categories (general guide)
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Obesity Range | 25%+ | 32%+ |
How to measure correctly
Neck
Measure just below the larynx (Adam’s apple), with tape level and snug but not compressing skin.
Waist
Measure at the narrowest point of the torso, or at navel level if no natural narrowing is visible.
Hip (women)
Measure around the widest part of the hips/glutes while standing naturally.
Height
Stand upright without shoes, heels against a wall, and look straight ahead.
Tips for better progress tracking
- Measure once per week, not daily.
- Take readings under similar conditions (morning, before meals).
- Track trend over 4–8 weeks instead of reacting to one data point.
- Pair BF% with strength, waist size, sleep quality, and energy levels.
What to do with your result
If your body fat percentage is above your target range, focus on sustainable habits: resistance training, high-protein meals, sufficient sleep, and consistent activity. If your percentage is already low, prioritize recovery and avoid aggressive calorie deficits that can reduce performance and hormone health.
FAQ
Is BMI the same as body fat percentage?
No. BMI only uses height and weight. Body fat percentage is a direct estimate of body composition and is generally more informative for fitness goals.
Can hydration affect results?
Yes. Hydration, sodium intake, bloating, and measurement technique can all shift circumference readings and estimated BF%.
How fast should body fat change?
A common sustainable pace is about 0.25% to 1.0% body weight loss per week when cutting, depending on starting point and training level.