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Calculators
BMI Calculator
Free online BMI calculator
Enter the values
Local processingResult
The result will appear here after you run the tool.
Press Ctrl or Command and Enter to run the tool.
About this tool
About this tool
BMI Calculator divides weight in kilograms by the square of height in meters, using the standard adult classification ranges. It accepts metric (cm and kg) or imperial (feet, inches, and pounds) input, shows the category from underweight to obesity class III, and computes the healthy weight range for the entered height. All math is local.
Check your body mass index in seconds. Enter height and weight in either metric or imperial units, and the calculator returns the BMI value, the weight category it falls into, and the healthy weight range for that height. Use it as a general screening number, not a medical diagnosis.
Built for daily work
- Get a quick baseline number before starting a fitness plan.
- Check where your weight sits relative to standard categories.
- See the healthy weight range for a specific height.
- Track changes in BMI over time with consistent measurements.
How to use this tool
How to use this tool
Enter height and weight
Type your measurements into the fields for the selected system.
Read the result
The BMI value, its category, and the healthy weight range for your height are shown together.
Key features
Key features
Metric and imperial input
Enter cm and kg, or feet, inches, and pounds, with the fields adapting to your choice.
Standard categories
The result uses the conventional adult ranges from underweight through obesity class III.
Healthy range for your height
The calculator shows the weight range that corresponds to a normal BMI for the height you entered.
Local calculation
All math happens in your browser; measurements are never sent anywhere.
Practical use cases
Practical use cases
- Get a quick baseline number before starting a fitness plan.
- Check where your weight sits relative to standard categories.
- See the healthy weight range for a specific height.
- Track changes in BMI over time with consistent measurements.
- Prepare data for a doctor visit discussion.
Private by default
For local tools, input is processed in your browser and is not sent to application analytics.
Data processing noticeTechnical details
Technical details
ProcessingLocal browser processing
InputMetric or imperial units
FormulaWeight (kg) / height (m) squared
AudienceAdults 18 and older
Limitations and important notes
Limitations and important notes
- BMI does not distinguish muscle from fat and is not a diagnosis.
- The calculator is for adults; pediatric growth charts are out of scope.
- Pregnancy and some medical conditions affect BMI interpretation.
Frequently asked questions
Frequently asked questions
BMI relates weight to height using a simple formula. It is a screening measure for populations, not a direct measurement of body fat.
Not always. Muscular people can show a high BMI with low body fat. Interpret the number alongside other health markers.
The conventional adult range is 18.5 to 24.9. Below 18.5 is underweight and 25 or above is overweight, with obesity classes beyond 30.
No. Child BMI uses age and sex specific growth charts, which this tool does not implement.
Related guides and solutions
Related guides and solutions
How to calculate BMI correctly and what the number means
A practical guide to BMI with the [BMI calculator](tool:bmi-calculator): correct measurement, the formula in metric and imperial units, the standard ranges, and when BMI misleads.
Learn moreCalculate your BMI online with correct measurements
The [BMI calculator](tool:bmi-calculator) gives you an instant result in metric or imperial units, with the category and honest guidance about what the number can and cannot tell you.
Learn moreWhat local browser processing means for online tools
A transparent explanation of local tool processing, temporary browser memory, local storage, downloads, analytics boundaries, and cases that require remote services.
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