Body Fat Calculator
How to Estimate Body Fat Percentage
Body fat percentage is a more useful health metric than weight alone, because it distinguishes fat from muscle. This calculator uses the US Navy circumference method, which estimates body fat from a few simple tape measurements.
Enter your weight, height, and waist and neck circumference (plus hip for women) in centimeters. The Navy formula has been validated against hydrostatic weighing and is accurate to within about 3-4%. It is a practical way to track body composition changes without expensive scans.
Frequently Asked Questions
How accurate is the US Navy body fat method?
Studies show it is accurate to within about 3-4% compared with hydrostatic weighing. It is the most reliable method you can do at home with just a tape measure. For the most accurate result, measure at the same time of day and keep the tape snug but not tight.
What is a healthy body fat percentage?
For men, essential fat is about 2-5%, athletes typically sit at 6-13%, fit men 14-17%, and up to 24% is considered acceptable. For women, the ranges are higher: essential 10-13%, athletes 14-20%, fit 21-24%, acceptable up to 31%.
Why is body fat better than BMI?
BMI cannot tell fat from muscle, so muscular athletes often show as "overweight". Body fat percentage measures composition directly, which correlates more strongly with health risks. Using both together gives the clearest picture.