Body fat calculators
This hub holds the body fat calculators. All of them use the US Navy method, which needs only a tape measure. Enter your height and tape measurements in the calculator below to estimate your body fat. The worked example further down shows the steps with real numbers.
How it works
The male Navy formula takes the waist minus the neck in inches and finds its base 10 log. Multiply that by 86.010. Then subtract 70.041 times the base 10 log of height and add 36.76.
Worked example
A man who is 5 ft 11 in tall has a 36 inch waist and a 16 inch neck. Waist minus neck is 20 inches. The base 10 log of 20 is 1.30103, and 1.30103 × 86.01 = 111.902. The base 10 log of 71 is 1.85126, and 1.85126 × 70.041 = 129.664. 111.902 − 129.664 + 36.76 = 19.00, which rounds to 19.0 percent. That is in the average range.
Common questions
What is a healthy body fat percentage?
Ranges depend on sex and goals. The American Council on Exercise lists essential fat, athletes, fitness, average and obesity ranges. Enter your own measurements in the calculator above to see your result.
Why does the waist matter more than weight?
Waist size reflects fat carried around the middle, while body weight cannot tell fat from muscle. Enter your own measurements in the calculator above to see your result.
Can I enter centimeters?
Yes. Switch the units and the page converts everything to inches before it does the math. Enter your own measurements in the calculator above to see your result.
How accurate is the Navy method?
It is an estimate. It is usually within a few percentage points of more precise methods, and careful measuring matters. Enter your own measurements in the calculator above to see your result.
Where do I place the tape?
Measure the neck just below the larynx. For men measure the waist at the navel. For women measure the waist at its narrowest point and the hips at their widest. Keep the tape snug and level without squeezing. Enter your own measurements in the calculator above to see your result.