BMI Calculator
Calculate your BMI (body mass index), its category, and the healthy weight range for your height. A simple starting point for weight awareness.
BMI = weight(kg) ÷ height(m)². A reference indicator.
How is BMI calculated?
BMI (body mass index) is your weight in kilograms divided by the square of your height in metres: BMI = weight ÷ (height × height). For example, 170 cm (1.7 m) and 65 kg gives 65 ÷ (1.7 × 1.7) ≈ 22.5, which is 'normal'. It doesn't measure body fat directly, but it's a quick check of whether your weight is proportionate to your height.
Categories (WHO)
- Underweight: below 18.5
- Normal: 18.5 – 24.9
- Overweight: 25 – 29.9
- Obese: 30 and above
The limits of BMI
- Very muscular people can score a high BMI despite low body fat.
- It isn't directly applicable to older adults, growing teens, or during pregnancy.
- It ignores fat distribution (e.g. belly fat), so pair it with waist measurements.
What is the healthy range?
This calculator also shows the weight range that corresponds to a BMI of 18.5–24.9 for your height. Falling inside it is generally considered a healthy weight, but no single number defines health — treat BMI as one reference among several.
The height and weight you enter are calculated in your browser and never sent to a server.
Read the Privacy Policy →Frequently asked questions
What is the BMI formula?
Weight in kg divided by height in metres squared. Convert cm to metres first. e.g. 170 cm and 65 kg → 65 ÷ 1.7² ≈ 22.5.
What is a normal BMI range?
The WHO considers 18.5–24.9 normal. Some Asian guidelines treat 23 and above as overweight, so use it as a reference.
Can my BMI be normal but health still be a concern?
Yes. BMI doesn't capture fat distribution or muscle mass. Waist size and metabolic markers should be checked separately.
Is my information stored?
No. Height and weight are calculated in your browser and never sent to or stored on a server.