BMI Calculator

Calculate your Body Mass Index (BMI) in metric or imperial units and see which WHO weight category you fall into: underweight, normal, overweight or obese.

Your BMI
22.9
Normal weight
BMI rangeCategory
Below 18.5Underweight
18.5 – 24.9Normal weight
25 – 29.9Overweight
30 and aboveObese

BMI is a screening measure only and doesn't account for muscle mass, age or body composition.

How it works

BMI = weight(kg) ÷ height(m)². For imperial units, weight in pounds and height in inches are converted first (1 lb = 0.453592 kg, 1 in = 0.0254 m). Categories: <18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, ≥30 obese.

Frequently asked questions

Is BMI accurate for everyone?

BMI is a screening tool, not a diagnosis. It doesn't distinguish muscle from fat, so very muscular people may read as 'overweight' despite low body fat.

What is a healthy BMI range?

The WHO classifies 18.5–24.9 as the normal, healthy range for most adults.

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