Body fat calculator
Estimate body fat percentage from BMI, age and equation sex.
Formula
Fat % = 1.20×BMI + 0.23×age − 10.8×sex − 5.4
Estimated body fat ≈ 1.2×(23)+0.23×(30)-5.4
How to use
- Calculate BMI first if needed.
- Enter BMI, age and equation sex.
- Read the estimated percentage.
Examples
- BMI 25, age 30, male: 20.7%.
- BMI 20, age 40, female: 27.8%.
Frequently asked questions
Which method is used?
The 1991 Deurenberg adult equation, not a tape-measure method.
How precise is it?
The study reported a standard error of 4.1 percentage points; this is not a body-fat measurement.
What range is supported?
Adults 20–83 with BMI 13.9–40.9; the paper noted overestimation in obesity.
Sources
Updated: