BMI Calculator
Work out body mass index from height and weight, and see the healthy weight range for that height.
- Healthy range at this height
- 56.7–76.3 kg
- Underweight
- below 18.5
- Healthy weight
- 18.5 to 24.9
- Overweight
- 25 to 29.9
- Obese
- 30 and above
BMI is a rough screening figure, not a diagnosis. It does not distinguish muscle from fat, and it reads differently across ages, builds and ethnicities. Ask a doctor rather than a calculator.
How to use it
- Enter weight in kilograms.
- Enter height in centimetres.
- The BMI, its category and the healthy range appear below.
Questions
How much should I trust BMI? Less than its popularity suggests. It is a single ratio of weight to height squared, and it cannot tell muscle from fat. A very muscular person reads as overweight; someone with little muscle can read as healthy while carrying too much fat.
Do the categories apply to everyone? No. The thresholds come from studies of European populations, and several health bodies use lower cut-offs for people of South Asian descent, where risk rises at a lower BMI. Ask a doctor rather than a calculator.
Does it work for children? No. Children and teenagers are assessed against age and sex percentiles, not these fixed thresholds.