BMI Calculator
Calculate your Body Mass Index from height and weight. Supports metric and imperial units.
Runs locally — nothing is uploaded
How to use
- 1
Choose your unit system
Select metric (cm and kg) or imperial (feet, inches, and pounds) depending on how you measure height and weight.
- 2
Enter height and weight
Type your height and weight into the fields. Your BMI updates instantly — no button to press.
- 3
Read your BMI and category
Review your Body Mass Index score and whether it falls in the underweight, normal, overweight, or obese range for adults.
- 4
Use results as a screening guide
BMI is a quick health screening tool. Share the number with your doctor if you have questions about weight management or fitness goals.
Frequently Asked Questions
BMI is weight in kilograms divided by height in meters squared (kg/m²). For imperial units, height and weight are converted to metric first, then the same formula is applied.
For most adults, a BMI between 18.5 and 24.9 is considered normal. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is obese.
BMI does not distinguish muscle from fat, so athletes and very muscular people may score high despite low body fat. It is less reliable for children, elderly adults, and pregnant women.
No. All calculations run in your browser. Your measurements are never sent to a server.
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