BMI Calculator
Check your Body Mass Index, its category, and the healthy weight range for your height.
Your BMI
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Enter your weight and height
Underweight
Healthy weight
Overweight
Obesity class I
Obesity class II
Obesity class III
Healthy weight for your height
To reach a healthy BMI
BMI Prime
Adult BMI categories
| Category | BMI |
|---|---|
| Underweight | Below 18.5 |
| Healthy weight | 18.5 – 24.9 |
| Overweight | 25 – 29.9 |
| Obesity class I | 30 – 34.9 |
| Obesity class II | 35 – 39.9 |
| Obesity class III | 40 and above |
Source: World Health Organization. Under 20? Use a BMI-for-age percentile chart instead. See the full BMI chart by height →
Frequently asked questions
How is BMI calculated?
BMI is your weight in kilograms divided by your height in metres squared. In pounds and inches, it is 703 × weight ÷ height². For example, 70 kg at 1.75 m gives 70 ÷ 1.75² = 22.9.
What is a healthy BMI?
For adults, a BMI from 18.5 to 24.9 is considered a healthy weight. Below 18.5 is underweight, 25 to 29.9 is overweight, and 30 or more is obesity.
Is BMI different for men and women?
No. Adult BMI uses the same formula and the same categories for men and women. Women tend to carry more body fat than men at the same BMI, which BMI does not show.
Who should not rely on BMI?
BMI does not measure body fat directly, so it can mislead for athletes with a lot of muscle, older adults, and people who are pregnant. Children and teens under 20 need BMI-for-age percentiles instead. Some health bodies use lower cut-offs for people of South Asian, Chinese, and other Asian backgrounds.
What is BMI Prime?
BMI Prime is your BMI divided by 25, the upper limit of the healthy range. A value of 1.00 is the top of the healthy range; 0.74 to 1.00 is healthy.