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 2 | Wrist measurement (at fullest point) / 3.140 |
Factor 3 | Waist measurement (at naval) x 0.157 |
Factor 4 | Hip measurement (at fullest point) x 0.249 |
Factor 5 | Forearm measurement (at fullest point) x 0.434 |
Lean Body Mass | Factor 1 + Factor 2 - Factor 3 - Factor 4 + Factor 5 |
Body Fat Weight | Total 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 2 | Waist measurement x 4.15 |
Lean Body Mass | Factor 1 - Factor 2 |
Body Fat Weight | Total bodyweight - Lean Body Mass |
Body Fat Percentage | (Body Fat Weight x 100) / total bodyweight |