BMI Calculator
Enter your weight and height to see your BMI.
BMI is a quick screening measure of body weight relative to height. Enter weight and height (switch between kilograms/centimetres and pounds/inches). The tool classifies the result into underweight, normal, overweight, or obese bands using standard thresholds and shows reference ranges. All math is local to your browser.
How to use
- Choose metric (kg, cm) or imperial (lb, in).
- Enter your weight and height.
- Read your BMI to one decimal place and the matching category.
- Compare against the four standard bands shown below the result.
Examples
- 70 kg at 175 cm is a BMI of 22.9 (normal weight).
- 154 lb at 69 in is a BMI of about 22.7 (normal weight).
- 95 kg at 170 cm is a BMI of 32.9 (obese).
FAQs
- What is the BMI formula?
- BMI equals weight in kilograms divided by height in metres squared. The tool converts imperial units using the standard factors 0.45359237 kilograms per pound and 0.0254 metres per inch before applying the formula.
- What do the categories mean?
- Underweight is below 18.5, normal weight is 18.5 to 24.9, overweight is 25 to 29.9, and obese is 30 and above. These are the widely used adult thresholds for population screening.
- Does BMI account for muscle, age, or sex?
- No. BMI is a simple height to weight ratio. It does not distinguish muscle from fat, nor does it adjust for age or sex. Athletes and older adults may receive a classification that does not reflect their actual health status.
- Can I use it for children?
- BMI for children and teens uses age and sex specific percentiles rather than the adult cut offs shown here. Consult a paediatric growth chart or healthcare professional for anyone under 20.
- Is the data I enter stored or sent anywhere?
- No. The calculation happens entirely in your browser. Your measurements never leave your device.
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