BMI Calculator
Enter height and weight to see your BMI, category and healthy weight range.
For reference only. Muscle mass and age matter. Talk to a doctor about your health.
About the BMI Calculator
BMI is your weight divided by your height squared. Choose your country at the top to enter height and weight in feet/inches and pounds (US, Canada), stone and pounds (UK) or centimeters and kilograms. Choose the classification you want: the WHO international standard (overweight from 25, obese from 30) or the Asia-Pacific standard used in Korea (overweight from 23, obese from 25), which accounts for higher health risk at lower BMI in Asian populations. The tool also shows a healthy weight range for your height and how far you are from it.
Frequently asked questions
How is BMI calculated?
BMI = weight (kg) ÷ height (m)². For example, 170 cm and 70 kg gives 70 ÷ (1.7 × 1.7) = about 24.2.
Why are there two standards?
The WHO international categories call BMI 25 or more overweight and 30 or more obese. Korea follows the Asia-Pacific guidelines: 23-24.9 is 'at risk' (overweight), 25-29.9 is obese class 1, 30-34.9 is class 2 and 35 or more is class 3.
Is BMI an accurate measure of health?
No. BMI cannot tell muscle from fat, so very muscular people can score high. It also does not apply to children, teenagers and pregnant women. Treat it as a rough guide and talk to a doctor about your health.
How is the standard weight calculated?
It is the weight at BMI 22: height in meters squared × 22.
Is what I enter stored on a server?
No. Everything is calculated inside your browser. Nothing you enter is sent to or stored on any server.