BMI calculator
Calculate adult BMI from height in cm and weight in kg in your browser, with the standard range shown.
Height and weight you type never leave this device.
How to use it
- 1
Type your height in centimeters
Enter your height in centimeters, for example 170. Only centimeters and kilograms are supported.
- 2
Type your weight in kilograms
Enter your weight in kilograms, for example 65.5. Both numbers must be greater than zero.
- 3
Read the BMI and the range
Your BMI and the name of its range appear under the boxes at once, and the matching row of the range list is highlighted.
- 4
Check the standard used
The page names the classification it uses and lists every range. Change a number to see how the result moves.
Common use cases
Security and privacy
Your height and weight stay on your device
BMI is calculated by browser code on your device while you type. No upload route exists for this tool, no request carries your height or weight, and nothing is saved after you close the tab. Health numbers are personal, so they are never sent to anyone.
Supported inputs and outputs
What it uses
- Height in centimeters
- Weight in kilograms
- BMI as weight divided by height in meters squared
- WHO adult classification in the English version
FAQ
Are my height and weight uploaded?
No. The calculation runs inside your browser. No request that carries your height or weight is sent to Frisbly or anyone else.
Is this a medical result?
No. BMI is a general guide for adults based only on height and weight. It does not measure body fat, muscle, or health, so ask a doctor about your health.
Which ranges does the English version use?
The WHO adult classification: under 18.5 is underweight, 18.5 to 24.9 is normal, 25 to 29.9 is pre-obese, 30 to 34.9 is obesity class I, 35 to 39.9 is class II, and 40 or more is class III.
Why do the Korean ranges differ?
The Korean version uses the Korean Society for the Study of Obesity ranges, where 23 to 24.9 is already pre-obese and 25 or more is obesity, which is lower than the WHO limits.
Can I use it for children?
No. These ranges are for adults. Children and teenagers are judged with growth charts for their age and sex, which this tool does not include.