BMI Calculator
Calculate your Body Mass Index from height and weight in metric or imperial units, and see the healthy weight range for your height.
How it works
- 1
Select metric or imperial units, then enter your height and weight — the BMI updates as you type.
- 2
See your BMI to one decimal place alongside the standard WHO category for that value.
- 3
Check the healthy weight range shown for your height as an additional reference point.
Questions
How is BMI calculated?
BMI = weight (kg) ÷ height (m)². Imperial inputs are converted to metric before the calculation.
What do the categories mean?
The four WHO categories are: below 18.5 — underweight; 18.5 to 24.9 — healthy weight; 25 to 29.9 — overweight; 30 and above — obese. These cut-offs are the same internationally used thresholds.
Is BMI a reliable health measure?
BMI is a simple population-level screening tool, not a medical diagnosis. It does not account for age, sex, ethnicity, muscle mass, or fat distribution, and it can mis-classify both athletes and older adults. Consult a healthcare professional for an individual health assessment.
Is my data saved or sent anywhere?
No. The calculation runs entirely in your browser. Nothing you enter is stored or transmitted.
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