Body Fat Calculator
Estimate body fat percentage with the US Navy method using tape measurements.
Last updated: August 2026
Body fat
12.3%
Category
Athletic
Ideal fat range
10–18%
for general health
US Navy method. Tape should be snug but not tight; measure the neck just below the larynx. Estimates vary ±3%.
How it works
Navy method (male): 495 ÷ (1.0324 − 0.19077·log₁₀(w−n) + 0.15456·log₁₀(h)) − 450, in inches.
Example: waist 90 cm, neck 40 cm, height 178 cm → ≈ 12.3%.
Frequently Asked Questions
How accurate is the US Navy body fat method?
Within about ±3% of hydrostatic weighing when measurements are taken correctly. The tape must be snug, and the neck is measured just below the larynx.
What is a healthy body fat percentage?
For men, 10–20% is considered fit and 6–13% is athletic. For women, 18–28% is fit and 14–21% is athletic, since women need more essential fat.
Why is BMI different from body fat percentage?
BMI only uses height and weight, so muscular people score high. Body fat percentage measures actual fat, making it more accurate for athletic builds.
What is visceral fat and why does it matter?
Visceral fat wraps around organs inside the belly. Even at a normal body fat percentage, high visceral fat raises the risk of heart disease and diabetes.