BMI calculator
Enter your height and weight to see your body mass index (BMI) and where it sits in the World Health Organization adult ranges.
Your body mass index
–kg/m²
Within the recommended range
Adult ranges
- Under 18.5Below the recommended range
- 18.5 to 24.9Within the recommended range
- 25 to 29.9Above the recommended range
- 30 and overAbove the recommended range
Thresholds: World Health Organization, for adults.
BMI is an arithmetic classification, not a medical assessment.
Start by measuring, across your organisation
We build programmes for organisations that begin with functional tests and progress by measurement. Individual results are never shared with the employer.
Common questions
How is body mass index calculated?
Your weight in kilograms is divided by the square of your height in metres. For 70 kg and 1.75 m, that is 70 / (1.75 x 1.75) = 22.9 kg/m².
Where do the 18.5, 25 and 30 thresholds come from?
They are the thresholds the World Health Organization uses for adults. On this page we show 18.5 to 24.9 as the recommended range. Children and adolescents use a different method, so this tool does not suit them.
What does body mass index not show?
The calculation uses only height and weight, so it cannot separate muscle from fat or show where fat sits on the body. Other measures such as waist circumference add information.