What is the U.S. Navy method?
This is a method developed by the U.S. Navy to estimate body fat percentage with just a tape measure, without a body fat scale or bioelectrical impedance (BIA) analyzer. Men need neck and waist circumference, while women need neck, waist, and hip circumference, along with height. Measure the neck just below the larynx (Adam's apple), the waist at navel height, and the hip at its widest point.
Body fat percentage ranges (for reference)
- Men: ~5% essential fat, 6-13% athletes, 14-17% fitness, 18-24% average, 25%+ obese
- Women: ~13% essential fat, 14-20% athletes, 21-24% fitness, 25-31% average, 32%+ obese
These ranges are commonly cited by organizations such as the American College of Sports Medicine (ACSM) and can vary somewhat by age and ethnicity.
A note of caution
This calculator estimates body fat percentage from tape-measure readings alone, so it can be less accurate than a bioelectrical impedance (BIA) analyzer, hydrostatic weighing, or a DEXA scan (some studies report a margin of error of around Β±3-5 percentage points versus true body fat). If you need an accurate body composition reading, consider a precise test at a specialized facility.
Frequently Asked Questions
How do I measure accurately with a tape measure?
Keep the tape snug against the skin without pulling it tight, and measure after exhaling. Measuring at the same time of day (e.g. first thing in the morning, before eating) makes it easier to track changes accurately over time.
How is body fat percentage different from BMI?
BMI is calculated from height and weight alone, so it can't distinguish between muscle and fat. Body fat percentage separately estimates the proportion of fat in your body, so someone with a lot of muscle mass can have a high BMI but a low body fat percentage. Curious about your BMI? Check out the BMI Calculator too.