How to Calculate BMI
What is BMI?
Body Mass Index (BMI) is a screening number calculated from your weight and height. It provides a quick indicator of whether someone may be underweight, normal weight, overweight, or obese. BMI is a population-level tool — it does not diagnose individual health.
Step-by-Step Guide
- 1Measure weight in kg and height in metres
- 2Square the height: h²
- 3Divide weight by height squared: BMI = weight / height²
- 4Compare result to WHO BMI categories
Worked Examples
Input
Height 1.75m, weight 68kg
Result
BMI = 22.2
Normal weight range
Input
Height 5'8", weight 150 lbs
Result
BMI = 22.8
Normal weight range
Input
Height 1.80m, weight 95kg
Result
BMI = 29.3
Overweight (close to obese threshold)
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