BMI Calculator
Work out your Body Mass Index from your weight and height. Switch between metric and imperial units to see your BMI and which weight category it falls into.
How to use the BMI calculator
- Choose metric (kg and cm) or imperial (lb and inches) units.
- Enter your weight and your height.
- Read your BMI and its weight category on the scale below.
Examples
Metric example
70 kg, 175 cm
BMI 22.9 (Normal weight)
Imperial example
154 lb, 69 in
BMI 22.7 (Normal weight)
Frequently asked questions
What is BMI?
Body Mass Index is a number from your weight and height that estimates whether your weight is in a healthy range. Metric BMI is weight in kilograms divided by height in metres squared.
What are the BMI categories?
The World Health Organization uses: under 18.5 is underweight, 18.5 to 24.9 is normal weight, 25 to 29.9 is overweight and 30 or above is obesity.
What is a healthy BMI range?
For most adults a BMI between 18.5 and 24.9 is considered the healthy range. The right target can differ with age, sex and ethnicity, so use it as a guide rather than a rule.
Is BMI accurate for everyone?
Not always. BMI does not separate muscle from fat, so athletes and very muscular people can read as overweight while having low body fat. It also ignores fat distribution.
What are the limitations of BMI?
BMI is a quick screening tool, not a diagnosis. It can be misleading for muscular builds, older adults, pregnant people and children, who use age and sex specific charts instead.
Is my data sent anywhere?
No. The BMI calculation runs entirely in your browser. Your weight and height are never uploaded or stored.
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