BMI Calculator
Enter height and weight to get your Body Mass Index, its WHO category, and the healthy weight band for your height.
How to use
- Enter your height in centimeters and weight in kilograms.
- Your BMI and WHO category appear instantly.
- Check the healthy weight range shown for your height.
Frequently asked questions
How is BMI calculated?
BMI = weight (kg) ÷ height² (m²). For example, 70 kg at 175 cm gives 70 ÷ 1.75² ≈ 22.9. It is a screening ratio, not a direct measure of body fat.
What are the WHO BMI categories?
The World Health Organization classifies adults as: Underweight (< 18.5), Normal weight (18.5–24.9), Overweight (25.0–29.9), and Obesity in three classes (I: 30–34.9, II: 35–39.9, III: ≥ 40).
Why is BMI criticized for athletes?
Muscle is denser than fat, so very muscular people can score “overweight” while carrying little fat. BMI also says nothing about fat distribution — waist measurements fill that gap better.
Do the same ranges apply to children?
No. Children and teenagers are assessed with age- and sex-specific BMI percentiles, not the adult cutoffs. This tool implements the adult WHO standard only.
What is a healthy weight range?
The weight range that keeps your BMI between 18.5 and 24.9 for your height — the calculator shows it directly. It is a wide band because healthy bodies come in many shapes.