BMI calculator

Enter your height and weight to find your body mass index and see the standard range it falls in. It is a quick guide, not medical advice.

Your BMI
category
healthy weight range

How BMI is calculated

BMI = weight (kg) ÷ height (m)²

Below 18.5 is underweight, 18.5 to 24.9 is the normal range, 25 to 29.9 is overweight, and 30 or above is in the obese range. The healthy weight range is worked out from your height.

FAQs about BMI

What is BMI?

Body mass index is a simple measure that compares your weight to your height. It gives a single number used to place adults into broad weight ranges from underweight to obese.

How is BMI calculated?

BMI is your weight in kilograms divided by your height in metres squared. For example, 70 kg at 1.75 m is 70 ÷ (1.75 × 1.75), which is about 22.9.

What are the BMI ranges?

For adults, below 18.5 is underweight, 18.5 to 24.9 is the normal range, 25 to 29.9 is overweight, and 30 or more is in the obese range.

Is BMI accurate for everyone?

BMI is a rough guide, not a diagnosis. It does not separate muscle from fat, so athletes and some body types can read high or low. Treat it as one signal among many.

Should I rely on BMI alone?

No. BMI is useful for a quick check, but waist size, activity, diet, and a doctor’s advice give a fuller picture of your health.

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