Body Fat Calculator

Estimate your body fat percentage with the U.S. Navy method.

Measuring Body Fat with a Tape Measure

The U.S. Navy circumference method estimates body fat percentage from a few tape measurements — no calipers or scans needed. Developed at the Naval Health Research Center, it remains the military's standard field assessment and is accurate to roughly ±3–4 % for most physiques.

How to Measure Correctly

  • Neck: just below the larynx, tape sloping slightly downward at the front.
  • Waist: men at the navel, women at the narrowest point — relaxed, after a normal exhale.
  • Hips (women only): at the widest point of the buttocks.

Measure in the morning, unclothed, tape snug but not compressing skin. Take each measurement twice and average.

Healthy Body Fat Ranges

CategoryMenWomen
Essential fat2–5 %10–13 %
Athletic6–13 %14–20 %
Fit14–17 %21–24 %
Average18–24 %25–31 %
Obese25 %+32 %+

Women naturally carry more essential fat than men — it supports hormone function and is not something to minimize.

For clinical accuracy, DEXA scans or hydrostatic weighing are the reference methods.

Frequently Asked Questions

How accurate is the Navy method?
Typically within ±3–4 % of DEXA results when measurements are taken carefully. Consistency matters most: measured the same way over time, it tracks changes well.
Why does it need hip measurement for women?
Women store proportionally more fat at the hips; including that circumference significantly improves the formula’s accuracy for female physiques.
Is body fat percentage better than BMI?
It answers a different question. BMI classifies weight relative to height; body fat percentage describes composition. A muscular person can have high BMI and low body fat — composition tells the truer story.
How fast can I lower my body fat?
Sustainable fat loss runs about 0.5–1 % of body fat per month with a moderate calorie deficit and resistance training to preserve muscle.