Navy Body Fat Calculator
Estimate your body fat percentage with the U.S. Navy method — all you need is a tape measure.
The U.S. Navy body fat formula is one of the most popular ways to estimate body fat at home because it needs nothing more than a tape measure — no calipers, scales or clinic visit. It uses the circumference of your neck, waist (and hips for women) along with your height to estimate body fat percentage.
Enter your measurements below to get your body fat percentage, your category (athletic, fitness, average, etc.), and personalised next steps. For the most accurate result, measure in the morning before eating and keep the tape snug but not compressing the skin.
How the Navy method works
The Navy formula is based on the relationship between body fat and where you carry circumference — primarily the waist relative to neck and height. For men it uses neck and waist; for women it adds hip measurement, since women tend to store more fat around the hips. It is a regression equation validated against more expensive methods, and for most people it lands within a few percentage points of a DEXA scan.
How to measure accurately
Accuracy lives in the tape. Neck: measure just below the larynx (Adam’s apple), tape sloping slightly down at the front. Waist: men measure at the navel; women at the narrowest point. Hips (women): the widest part of the buttocks. Keep the tape level and snug, take each measurement twice, and average them. Measuring at the same time of day each time makes your tracking far more reliable than any single reading.
What your number means — and its limits
Use the result as a trend tool, not gospel. The Navy method can be less accurate for very lean or very muscular people, and circumference-based formulas cannot tell muscle from fat directly. What matters most is the direction over weeks: a waist that shrinks while strength holds means you are losing fat, regardless of the exact percentage. Re-measure every 2–6 weeks depending on how focused your training phase is.
Frequently Asked Questions
How accurate is the Navy body fat calculator?
For most people the Navy method lands within about 3–4% of a DEXA scan, which is good for a free, tape-measure method. It can be less accurate for very lean or very muscular individuals. Use it to track the trend over time rather than as an exact figure.
What measurements do I need?
Height, neck and waist circumference for men; women also add hip circumference. That is all — no scales or calipers required.
Where exactly do I measure my waist?
Men should measure at navel level; women at the narrowest point of the waist. Keep the tape level and snug without compressing the skin, and measure in the morning before eating for consistency.
What is a healthy body fat percentage?
General ranges: men — athletic 6–13%, fitness 14–17%, average 18–24%. Women — athletic 16–20%, fitness 21–24%, average 25–31%. Women naturally carry more essential fat than men. The calculator shows your category with your result.