BMI calculator
Calculate your Body Mass Index from height and weight, in metric or imperial, with your healthy-weight category.
BMI is a general guide and doesn't account for muscle, age or build. It is not medical advice.
How to use
Choose metric or imperial units, enter your weight and height, and your Body Mass Index (BMI) is calculated instantly along with the category it falls into — underweight, normal, overweight or obese. BMI is a quick screen that relates your weight to your height.
The coloured scale shows where your number sits across the standard ranges, so you can see at a glance how close you are to the next band. Everything is computed locally in your browser, so your figures stay private.
Treat BMI as a rough guide rather than a diagnosis: it doesn't distinguish muscle from fat and doesn't account for age, sex or body composition. For health decisions, talk to a medical professional.
Examples
Enter 70 kg and 175 cm to get a BMI of about 22.9 — in the normal range.
Switch to pounds and feet/inches to calculate without converting first.
See which weight would move you into the next BMI band to set a realistic target.
Frequently asked questions
How is BMI calculated?
BMI is your weight in kilograms divided by your height in metres squared (kg/m²). The imperial option converts your input for you.
What is a healthy BMI?
A BMI between 18.5 and 24.9 is generally considered the healthy range. Below 18.5 is underweight, 25–29.9 is overweight, and 30+ is obese.
Is BMI accurate for everyone?
No. It doesn't account for muscle mass, age, sex or fat distribution, so athletes and some body types can be misclassified. Use it as a general guide only.
Is my data stored?
No. The calculation runs in your browser and nothing you enter is saved or sent anywhere.
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