If you are unable to use our Body Fat Calculator, or if you are interested in how your Body Fat Percentage is calculated, this page has the mathematical Body Fat Formula.

The best time to use this formula, is in the morning. Your body weight and waist measurements are the most accurate just after you wake up from 7-8 hours of sleep.

The formula below will not calculate your exact body fat percentage. The most accurate way is underwater weighing, but this formula should give you a consistent measurement you can use as a guideline so you can determine if you're losing body fat and/or muscle.

Body Fat Formula For Women
Factor 1(Total body weight x 0.732) + 8.987
Factor 2Wrist measurement (at fullest point) / 3.140
Factor 3Waist measurement (at naval) x 0.157
Factor 4Hip measurement (at fullest point) x 0.249
Factor 5Forearm measurement (at fullest point) x 0.434
Lean Body MassFactor 1 + Factor 2 - Factor 3 - Factor 4 + Factor 5
Body Fat WeightTotal bodyweight - Lean Body Mass
Body Fat Percentage(Body Fat Weight x 100) / total bodyweight
 
Body Fat Formula For Men
Factor 1(Total body weight x 1.082) + 94.42
Factor 2Waist measurement x 4.15
Lean Body MassFactor 1 - Factor 2
Body Fat WeightTotal bodyweight - Lean Body Mass
Body Fat Percentage(Body Fat Weight x 100) / total bodyweight