Body Fat Calculator
Enter a few tape measurements to estimate body fat percentage by the US Navy method — no calipers needed.
Reviewed by the OmniCalc teamMethod verified 2026-07-01
18.37%
Body fat 18.37 percent- Category
- Average
- Body fat
- 18.37
Show steps
- Waist − neck = 90 − 40 = 50 cm.
- BF% = 495 ÷ (1.0324 − 0.19077·log₁₀(50) + 0.15456·log₁₀(180)) − 450 = 18.4%.
How to use the body fat calculator
- 1Pick your sex and enter height, neck and waist in cm (women also add hip).
- 2Optionally add your weight to see estimated fat and lean mass.
- 3Read your body fat percentage and fitness category.
Track the trend, not the digit
A tape estimate is best used to watch change over weeks. Measure at the same time of day, in the same spots, and compare the direction — a steady fall of a point or two is the signal that matters, not any single reading.
Frequently asked questions
How accurate is the US Navy method?
For most people it lands within about 3–4 percentage points of a clinical measurement, which is remarkable for a tape measure. It is a good tracking tool: measure the same way each time and watch the trend rather than fixating on a single number.
Where do I measure?
Neck below the larynx, waist at the navel, and for women the hips at the widest point. Keep the tape level and snug without compressing the skin, and measure relaxed after a normal breath.
What is a healthy body fat percentage?
Rough ranges differ by sex. For men, roughly 6–17% is athletic to fit and 18–24% is average; for women it is about 14–24% and 25–31% respectively. Essential fat sits below those and is not a target.