What is a BMI Calculator?
A BMI Calculator works out your body mass index from your height and weight and shows which weight category it falls in, using both WHO and Indian guidelines.
BMI is a quick screening number, not a diagnosis. Indian guidelines use lower cut-offs than WHO because South Asians tend to have higher health risks at a lower BMI. BMI does not tell muscle from fat, so athletes may read high.
How to use the BMI Calculator
- Enter weight.
- Enter height.
- Tap Calculate to see the result.
- Tap Reset to clear the fields and try again.
Who should use it
- Adults checking whether their weight is in a healthy range
- People starting a fitness or weight-loss plan
- Anyone tracking changes over time
Key terms
- BMI
- Weight in kilograms divided by height in metres squared.
- WHO categories
- Normal is 18.5 to 24.9.
- Indian guidelines
- Normal is 18.5 to 22.9, overweight 23 to 24.9 and obese 25 or above.
Frequently asked questions
Is BMI accurate for everyone?
No. It can misread very muscular people, older adults and pregnant women.
Why are Indian cut-offs lower?
Studies show higher risk of diabetes and heart disease at lower BMI levels in South Asians.
Can children use this?
No. Children need age- and sex-specific BMI charts.
Is my data stored?
No. Nothing you enter leaves your device.
Last updated: 1 November 2026