BMI Calculator
Enter your height and weight in metric or imperial units to calculate your Body Mass Index (BMI), see which category it falls in, and find the healthy weight range for your height.
What BMI measures
Body Mass Index is your weight in kilograms divided by the square of your height in metres. It's a quick screening number used worldwide to flag whether your weight is in a range associated with good health for your height.
The standard categories are: under 18.5 is underweight, 18.5 to 24.9 is a normal or healthy weight, 25 to 29.9 is overweight, and 30 or above is in the obese range.
What BMI doesn't tell you
BMI doesn't distinguish muscle from fat, so very muscular people can score high without excess fat. It also doesn't account for body-fat distribution, age, sex or ethnicity, all of which affect health.
Treat BMI as a starting point for a conversation with a healthcare professional, not a diagnosis. Waist measurement and other checks add important context.
Frequently asked questions
How is BMI calculated?
BMI equals weight in kilograms divided by height in metres squared. In imperial units, it's 703 × weight in pounds ÷ height in inches squared. This calculator handles both.
What is a healthy BMI?
A BMI between 18.5 and 24.9 is generally considered healthy for adults. The calculator shows the weight range that corresponds to this for your height.
Is BMI accurate for athletes?
Not always. Because muscle weighs more than fat, athletic and muscular people may have a high BMI despite low body fat. Use it as a general guide only.