BMI Calculator
Calculate your Body Mass Index (BMI) in metric or imperial units and see the WHO weight category and healthy weight range for your height.
This tool runs entirely in your browser.
Loading tool…
How to use the BMI Calculator
- 1Choose metric or imperial units.
- 2Enter weight and height.
- 3Read your BMI and category.
What is the BMI Calculator?
BMI = weight (kg) ÷ height (m)². WHO categories for adults: under 18.5 underweight, 18.5–24.9 healthy, 25–29.9 overweight, 30 and above obesity.
Frequently asked questions
Is BMI accurate for athletes?
Not always — BMI cannot tell muscle from fat, so muscular people may be classed as overweight.
Is the BMI Calculator free and private?
Yes. The BMI Calculator is free, needs no account, and runs entirely in your browser. What you type is never sent to a server or stored.
Related tools
All calculators →- BMR CalculatorEstimate calories burned at rest and per day.
- Weight ConverterConvert kg to lbs, grams to ounces, stone to kg.
- Length ConverterConvert km to miles, cm to inches, feet to meters.
- Age CalculatorCalculate exact age in years, months and days.
- Percentage CalculatorWork out percentages of numbers.
- Percentage Increase CalculatorFind the percentage increase or decrease.