The Body Fat Calculator is a tool that provides an estimate of one's total body fat percentage based on certain bodily measurements. Should you wish to utilize the SI (International System of Units) instead, you may click on the "Metric Units" tab. Taking the measurements with a precision of up to ¼ inch (0.5 cm) will give you the most accurate results. The U.S. Navy method is mainly used in this tool for determining body fat but it also gives an alternative BMI-based estimation which is described down below.