BMI Calculator
Calculate your body mass index and find your ideal weight.
How is it calculated?
BMI = weight (kg) / height (m)²
Example: 65 kg / (1.70 m)² = 22.49
- • < 18.5: Underweight
- • 18.5 - 24.9: Normal weight
- • 25.0 - 29.9: Overweight
- • 30.0 - 34.9: Class 1 obesity
- • 35.0 - 39.9: Class 2 obesity
- • ≥ 40.0: Class 3 obesity
More about this calculation
Body Mass Index (BMI) is a number that estimates body fat from your height and weight, and is used to screen adults for underweight, normal weight, overweight and obesity.
BMI is calculated by dividing your weight in kilograms by the square of your height in meters. The World Health Organization describes a BMI below 18.5 as underweight, 18.5 to 24.9 as normal, 25 to 29.9 as overweight and 30 or above as obesity. BMI does not measure body fat directly, so it can misclassify athletes, very muscular people, pregnant women, children and older adults. Use it as a general guide together with professional medical advice.
Frequently asked questions
How is BMI calculated?
BMI equals weight in kilograms divided by height in meters squared. For example, a person of 70 kg and 1.75 m has a BMI of about 22.9.
What is a healthy BMI range?
For most adults a BMI between 18.5 and 24.9 is considered healthy, below 18.5 is underweight and 25 or above is overweight.
Is BMI accurate for everyone?
No. Athletes and muscular people may show a high BMI despite low body fat, and BMI is not reliable for children, pregnant women or older adults.