Free Body Fat % Calculator (BMI Method)
Estimate your body fat percentage using the BMI-based method. This formula uses your BMI and age to estimate body fat.
lbs
ft
in
years
Estimated Body Fat %
21.7 %
BMI25.8
Lean Mass %78.3 %
Estimated Body Fat % vs Weight
BMI-Based Body Fat Estimation (Male)
Body Fat % = 1.20 x BMI + 0.23 x Age - 16.2
This formula was developed by Deurenberg et al. and provides an estimate of body fat percentage using BMI and age.
Note: This is the male formula. The female formula uses different constants (1.20 x BMI + 0.23 x Age - 5.4).
Example Calculation
A 30-year-old male, 180 lbs, 5'10".
- 01BMI = (180 x 703) / (70 x 70) = 25.8
- 02Body Fat = 1.20 x 25.8 + 0.23 x 30 - 16.2
- 03= 31.0 + 6.9 - 16.2 = 21.7%
Frequently Asked Questions
Learn More
Understanding BMI: What It Means and How to Calculate It
Learn what BMI is, how to calculate it, what the ranges mean, and the limitations of body mass index as a health metric. Comprehensive guide with formulas and context.