Calculate your BMI privately
Calculate your BMI for free in your browser, using documented WHO adult thresholds.
Calculate your adult BMI
A simple measure based on your weight and height. No result is a diagnosis.
Adult reference ranges
Adult thresholds: WHO (18.5 · 25 · 30). BMI is a screening measure, not a diagnosis.
This tool does not replace advice from a healthcare professional.
Your data stays in your browser.
How should BMI be read?
BMI is the ratio of weight to height squared. For adults, it provides a general screening measure. It does not account for muscle mass, age, pregnancy, or many individual circumstances.
A simple local tool
- Quickly check a weight reference
- See the formula and thresholds used
- Reset your data in one click
Frequently asked questions about BMI
Does BMI provide a diagnosis?
No. It is an adult screening measure, not a medical diagnosis. Ask a healthcare professional to interpret a result.
Is my data stored?
No. The calculation runs locally in your browser; no entered data is sent to the server.
Which thresholds are used?
The adult thresholds shown are those commonly used by the World Health Organization: 18.5, 25 and 30.