Use the BMI Calculator
Calculate your Body Mass Index (BMI) from your height and weight, in either metric (cm/kg) or imperial (ft-in/lb) units. BMI is a widely used screening measure that estimates whether your
- Free to use
- No signup
- Nothing to install
- Works in any modern browser
Illustration. Open the tool for the real thing.
What is the BMI Calculator?
Calculate your Body Mass Index (BMI) from your height and weight, in either metric (cm/kg) or imperial (ft-in/lb) units. BMI is a widely used screening measure that estimates whether your weight is in a healthy range relative to your height, and the result is shown alongside the standard BMI category.
BMI is a quick screening tool, not a full health diagnosis — it doesn't account for muscle mass, bone density, age or body composition, so athletes and very muscular people in particular may see a BMI that doesn't reflect their actual body fat level.
3 steps to your result
Open the tool and follow along. Nothing to install.
What you get
Enter height and weight in cm/kg or feet-inches/pounds.
See your BMI number and its standard category (underweight, normal, overweight, obese) immediately.
See the weight range considered healthy for your entered height.
No signup, and nothing you enter is stored or sent anywhere.
AZRS tools are free to open and use.
It opens in your browser, so there is nothing to download.
Used for
Pick one to see how it fits.
Anyone tracking general health
Get a quick, standard screening number as one data point among many.
Try it freePeople starting a fitness or weight goal
See your current BMI category as a baseline to track progress.
Try it freeHealthcare and fitness professionals
Quickly calculate a client's BMI without a separate spreadsheet.
Try it freeHow it compares
A plain look at this tool next to the usual alternative.
| This calculator | Desktop software | |
|---|---|---|
| Install | Nothing to install | Usually an app or program to install |
| Account | No signup | Depends on the product |
| Cost | Free to use | Free or paid, depends on the product |
Questions people ask
What is a healthy BMI?
A BMI between 18.5 and 24.9 is generally classified as 'normal weight' for most adults, though this varies by individual factors.
Is BMI accurate for athletes?
Not always — muscle weighs more than fat, so muscular individuals can show a higher BMI despite having low body fat.
How is BMI calculated?
BMI = weight (kg) ÷ height (m)². In imperial units: BMI = 703 × weight (lb) ÷ height (in)².
Is this BMI calculator free?
Yes, completely free with no signup.
Does BMI apply to children?
No, children and teens need age- and sex-specific BMI percentile charts, not the standard adult categories.
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Try the BMI Calculator now
Calculate your Body Mass Index (BMI) from your height and weight, in either metric. Free to use.
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