BMI Calculator
Calculate your Body Mass Index.
BMI
24.4
- WHO adult bandNormal weight
Underweight < 18.5 · Normal 18.5–24.9 · Overweight 25–29.9 · Obesity 30+. Same formula for men and women; not a diagnosis.
Body mass index from height and weight. The formula is the same for adult men and women; WHO adult bands are a screening chart, not a diagnosis. Muscle mass, age, and ethnicity change how BMI should be read.
Formula
Metric: BMI = kg / m². Imperial: BMI = 703 × lb / in².
How to calculate
- Enter weight and height in one unit system.
- The page converts to metres and kilograms if needed, then applies kg / m².
- Compare the number to WHO adult bands: underweight <18.5, healthy 18.5–24.9, overweight 25–29.9, obesity 30+.
Example
70 kg at 170 cm: 1.70² = 2.89, 70 / 2.89 ≈ 24.2 (healthy range).
Common mistake
Two people can share a BMI and not share the same body fat. Athletes often sit in “overweight” with low fat. This is not a men-versus-women formula.
FAQ
Is BMI different for women and men?
The calculation is the same. Body composition differs, so treat BMI as a screen, not a diagnosis.
What is a BMI chart?
Adult WHO bands: underweight <18.5, healthy 18.5–24.9, overweight 25–29.9, obesity 30+.
How do I calculate BMI?
Divide weight in kilograms by height in metres squared. Or use 703 × pounds / inches².