Body Fat Calculator
Estimate your body fat percentage from height, weight, age and sex — with a healthy-range guide.
Input
Enter age, height, and weight to estimate your body fat.
The Body Fat Calculator estimates your body fat percentage from your height, weight, age, and sex using the Deurenberg formula. It is a quick, equipment-free way to get a rough idea of body composition when calipers or a body scan are not available.
How to use the Body Fat Calculator
- Select your sex and enter your age.
- Enter your height and weight.
- Submit to calculate your estimated body fat percentage.
- Compare the result against typical ranges for your sex and age.
Frequently asked questions
- What formula does this calculator use?
- It uses the Deurenberg equation: BF% = 1.20 x BMI + 0.23 x age - 10.8 x sex - 5.4, where sex is 1 for male and 0 for female. For a 30 year old woman with a BMI of 24, that is 1.20 x 24 + 0.23 x 30 - 10.8 x 0 - 5.4 = about 30.3%.
- What is a healthy body fat percentage?
- General fitness ranges are often cited as roughly 14 to 24% for men and 21 to 31% for women, with athletes typically lower. Ranges vary by source and by age, so treat them as guidelines.
- How accurate is a formula-based estimate?
- Because it relies on BMI, age, and sex rather than a direct measurement, it can be off for very muscular or very lean people. Methods like DEXA or hydrostatic weighing are more accurate.
- Can I rely on this for health decisions?
- No. This is an estimate for general information only and not medical advice, so consult a qualified professional before acting on the number.