BMI Calculator
Calculate your BMI, see what category it falls in and find a healthy weight range for your height.
How to use: Enter your height and weight, pick metric or imperial units, and your BMI appears below.
How to use the BMI Calculator
Body mass index is a quick screening number calculated by dividing your weight in kilograms by your height in meters squared. It gives a rough idea of whether your weight is low, healthy or high for your height.
Choose metric or imperial units, then enter your height and weight. The calculator shows your BMI, the category it falls into and a healthy weight range for your height, based on the standard adult range of 18.5 to 24.9. A coloured scale shows where you sit between underweight, normal weight, overweight and obese.
BMI has real limits. It cannot tell muscle from fat, so very muscular people can score as overweight, and it ignores where body fat is stored. Age, sex, ethnicity and fitness all affect what is healthy for an individual. The standard adult categories also do not apply to children and teenagers, who are assessed against growth charts.
Use the result as a starting point for a conversation with a doctor, not as a diagnosis. Waist measurement, body fat percentage, blood pressure and activity levels give a fuller picture of health. The body fat and calorie calculators on this site can help you take the next step.
Frequently asked questions
What is a healthy BMI?
For most adults a BMI between 18.5 and 24.9 is considered the normal weight range.
Is BMI accurate for athletes?
Not always. Muscle weighs more than fat, so athletes can have a high BMI while having low body fat.
Can I use it for children?
No. Children and teens are assessed using age- and sex-specific growth percentiles, not adult BMI categories.