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Body Fat Percentage Estimator

Just enter your height, weight, age, and sex to estimate body-fat percentage with the Deurenberg formula. BMI, fat mass, and a category rating are shown too.

Input

Estimate your body-fat percentage from height, weight, age, and sex using the Deurenberg formula. It differs from a body-composition scale measurement, so use it as a rough guide only.

Sex
yrs
cm
kg

Result

Estimated body fat

17.7%

Male guideline category:Healthy

BMI

22.5

Category

Healthy

Est. fat mass

11.5 kg

Est. lean mass

53.5 kg

Body-fat guideline categories (Male)

CategoryBody-fat range
Low (lean)Under 10.0%
Healthy (you)10.0% – under 20.0%
Mildly overweight20.0% – under 25.0%
Obese25.0% and above

How it works

  • Enter your height, weight, age, and sex, and the tool estimates body-fat percentage with the Deurenberg formula: body fat (%) = 1.2 × BMI + 0.23 × age − 10.8 × sex (male 1, female 0) − 5.4. BMI is computed first from height and weight (weight in kg ÷ height in m²).
  • Estimated fat mass (kg) is calculated as weight × body-fat % ÷ 100, and lean body mass (kg) as weight − fat mass. Lean mass includes muscle, bone, and water.
  • The category ranges follow common guideline bands used by body-composition scales: for men, healthy 10–20%, mildly overweight 20–25%, obese 25%+; for women, healthy 20–30%, mildly overweight 30–35%, obese 35%+. Thresholds vary by organization and measurement method.
  • Because the Deurenberg formula estimates statistically from height, weight, age, and sex, results can differ from a real body-composition scale (bioelectrical impedance) or a DEXA scan. Errors tend to be larger for very muscular people or unusual body types.
  • It can also serve as a quick check for 'skinny fat'—a normal BMI (under 25) paired with a high body-fat percentage (roughly over 20–25% for men or over 30% for women).
  • This tool is only a general guide for health management, not a diagnosis or medical advice. For decisions about weight, body fat, or your health, consult a doctor or registered dietitian.