BMI Calculator – Calculate Body Mass Index Online
BMI Calculator
Calculate your Body Mass Index using your height and weight.
BMI Result
< 18.5
18.5 – 24.9
25 – 29.9
≥ 30
Free Online BMI Calculator
Calculate Body Mass Index (BMI) from your height and weight using metric or US units. The tool also shows the BMI category, BMI Prime, an estimated healthy weight range for the entered height, and Ponderal Index.
How to Calculate BMI
- Choose Metric (kg/cm) or US Units (lb/ft/in).
- Enter your weight and height.
- Click Calculate BMI.
- Review your BMI, category and additional calculated values.
- Use Copy Result to copy the result summary.
Understanding the Results
This calculator uses the adult BMI categories shown in the tool: underweight below 18.5, healthy weight 18.5–24.9, overweight 25–29.9 and obesity at 30 or above. BMI is a screening measure and does not directly measure body fat. Standard adult categories may not apply to children, teenagers, pregnancy, athletes with high muscle mass or some medical conditions.
Frequently Asked Questions
Can I use kilograms and centimeters?
Yes. Select Metric to enter weight in kilograms and height in centimeters.
Can I calculate BMI with pounds, feet and inches?
Yes. Select US Units to enter weight in pounds and height in feet and inches.
What additional results does this calculator show?
It shows BMI category, BMI Prime, an estimated healthy weight range and Ponderal Index.
What BMI range does this tool label as healthy for adults?
The calculator displays 18.5 to 24.9 as the healthy adult BMI range.
Does BMI directly measure body fat?
No. BMI is a screening measure based on height and weight and does not directly measure body fat.