Body Fat Calculator
Body fat percentage using the US Navy circumference method.
An estimate. DEXA and hydrostatic weighing are considerably more accurate.
How it works
The US Navy method estimates body fat from circumference measurements and height. It is free, needs only a tape measure, and lands within about 3-4 percentage points of a DEXA scan for most people.
Measure with the tape snug but not compressing, at the end of a normal breath out, and take each measurement three times. Most of the error in this method comes from inconsistent measuring, not from the formula.