BMI Calculator
Enter your weight and height in kilograms and centimetres or pounds and feet to get your Body Mass Index, its WHO category and the healthy weight range for your height.
Runs in your browser
How to use
- Choose metric or imperial units.
- Enter weight and height.
- Read your BMI, category and healthy range.
How it works
BMI = weight in kilograms ÷ (height in metres)². WHO adult categories: under 18.5 underweight, 18.5–24.9 healthy, 25–29.9 overweight, 30 and above obesity (classes I–III).
BMI is a simple screening tool at population level. It doesn't account for muscle mass, age, sex or body shape, and different thresholds are recommended for some populations. It is not a diagnosis.
Examples
- 70 kg, 1.75 m
- BMI 22.9 — healthy weight range 56.7–76.3 kg.
Common uses
- Checking weight status
- Tracking progress over time
Privacy & security
This tool runs entirely in your browser. Your files and text are never uploaded to our servers — processing happens on your device and results are created locally. How each tool handles files
Frequently asked questions
Is BMI accurate for athletes?
Not really: muscle is dense, so muscular people can have a high BMI without excess fat.
Can children use this calculator?
No. Children and teenagers need age- and sex-specific percentile charts.
How is the healthy weight range calculated?
It is the weight that gives a BMI between 18.5 and 24.9 at your height: 18.5 × height² to 24.9 × height², with height in metres. At 1.75 m that is 56.7 to 76.3 kg.
Last updated: