How to Calculate BMI: Formula, Chart and Examples
Learn how to calculate your Body Mass Index with the formula, the category chart and practical examples.
Body Mass Index (BMI) is the most used measure to see if your weight is healthy for your height. You only need your weight and height. In this guide we show the formula, the category chart and some examples.
1 The BMI formula
BMI = weight in kg ÷ (height in meters)². For example, for 70 kg at 1.75 m: 70 ÷ (1.75 × 1.75) = 22.9.
2 The category chart
Below 18.5: underweight. From 18.5 to 24.9: normal weight. From 25 to 29.9: overweight. 30 or more: obesity.
3 How to interpret your result
A BMI between 18.5 and 24.9 is considered a healthy range for most adults. If your result is outside it, you can also check the recommended weight range for your height.
4 Use the calculator
Enter your weight and height in the BMI calculator to get your result and category instantly, in metric or imperial units.
Try it with our free tool
BMI Calculator
Use the tool