Free BMI Calculator
Calculate your Body Mass Index and see which weight category it falls into.
| Underweight | Below 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25.0 – 29.9 |
| Obese | 30.0 and above |
Frequently Asked Questions
How is BMI calculated?
Metric: weight in kilograms divided by height in meters squared (kg/m²). Imperial: 703 × weight in pounds ÷ height in inches squared. Both formulas give the same result for the same body.
Is BMI an accurate measure of health?
BMI is a quick screening tool, not a diagnosis. It doesn't distinguish muscle from fat, so athletes and very muscular people are often misclassified as "overweight." Use it as one data point, not a verdict — talk to a doctor for a full picture.
Are the categories the same for everyone?
The standard WHO categories shown here are designed for adults. They don't apply the same way to children, teenagers, pregnant women, or very elderly or very muscular adults.
Is my data sent anywhere?
No. The calculation happens entirely in your browser. Nothing is transmitted or stored.