Body Fat Calculator
Estimate your body fat percentage with simple tape measurements
Enter your measurements to estimate body fat
Track Your Body Composition
Log measurements, track trends, and see how your body changes over time with Hypro.
How the U.S. Navy Body Fat Method Works
The U.S. Navy body fat formula estimates body fat percentage from simple circumference measurements — height, waist, neck, and hip (for women). It was developed by the Naval Health Research Center and is used by all branches of the U.S. military for fitness assessments.
The formula uses the logarithmic relationship between body circumferences and body density to estimate fat mass. While not as precise as a DEXA scan or hydrostatic weighing, the Navy method is accurate to within 3-4% for most individuals and requires nothing more than a tape measure.
How to Take Accurate Measurements
- Waist — Measure at your navel (belly button). Stand relaxed and do not suck in. Take the measurement at the end of a normal exhale.
- Neck — Measure just below the larynx (Adam's apple), with the tape sloping slightly downward at the front.
- Hip (women only) — Measure at the widest point of the buttocks/hips.
- Use a flexible, non-stretchy tape measure. Keep it snug but not tight enough to compress the skin.
Body Fat Categories
| Category | Men | Women |
|---|---|---|
| Essential Fat | 2-5% | 10-13% |
| Athletic | 6-13% | 14-20% |
| Fitness | 14-17% | 21-24% |
| Average | 18-24% | 25-31% |
| Above Average | 25%+ | 32%+ |
Frequently Asked Questions
How accurate is the Navy body fat method?
The Navy method is accurate to within 3-4% of DEXA scan results for most people. It works best for people with average body proportions. It may underestimate body fat in very muscular individuals.
Where should I measure my waist?
Measure at the navel (belly button) level. Stand relaxed, do not suck in your stomach, and take the measurement at the end of a normal exhale.
What is a healthy body fat percentage?
For men, 14-17% is the fitness range and 6-13% is athletic. For women, 21-24% is fitness and 14-20% is athletic. Essential fat is 2-5% for men and 10-13% for women.
How often should I measure body fat?
Every 4-8 weeks is sufficient. Body fat changes slowly and daily fluctuations create noise. Always measure under the same conditions.
Is body fat percentage better than BMI?
Yes, for most purposes. BMI cannot distinguish between muscle and fat. Body fat percentage gives a more accurate picture of body composition and health risk.
Related Free Tools
- BMR Calculator — Find how many calories your body burns at rest.
- Calorie Calculator — Calculate your TDEE and see how much to eat for your goal.
- Macro Calculator — Get your daily protein, fat, and carb targets.