BMI Calculator
Calculate your Body Mass Index and see your weight category.
Result
Results are estimates for general information only and are not professional advice.
What is BMI?
Body Mass Index (BMI) is a simple screening number that relates your weight to your height. It gives a quick, widely-used indication of whether your weight sits in a healthy range and is used by doctors, gyms and health services around the world as a first check — not as a full diagnosis.
How BMI is calculated
The formula is weight (kg) ÷ height (m)². The standard adult categories are: under 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, and 30 or above obese. This calculator applies the formula and instantly places your result in the matching category.
How to use this calculator
Enter your weight in kilograms and your height in centimetres, then press Calculate. You will see your BMI value and its category, along with the healthy weight range for your height so you can see how far you are from it.
Understanding your result
BMI is a useful general guide but it has limits: it does not distinguish muscle from fat, so very muscular people may read as overweight, and it is less reliable for children, athletes and the elderly. Treat it as a starting point and discuss any concerns with a healthcare professional.
Frequently Asked Questions
What is the BMI Calculator?
Calculate your Body Mass Index and see your weight category. It runs instantly in your browser and is completely free to use.
What do I need to enter to use the BMI Calculator?
The BMI Calculator asks for the following values (2): Weight (kg), Height (cm). Fill them in and the result appears immediately — the calculation runs on your own device, so nothing you type is sent to a server.
How accurate is the BMI Calculator?
The BMI Calculator uses standard, widely-accepted formulas, so its figures are reliable estimates for everyday planning. They are not a substitute for advice from a qualified professional.
Is the BMI Calculator free, and do I need an account?
Yes. The BMI Calculator — and every other calculator on Calculatis — is completely free, with no registration, no download and no limit on how often you use it.