BMI Calculator
Body mass index in metric or imperial
BMI is a rough screening measure, not a diagnosis of body fat or overall health. It does not distinguish muscle from fat and varies in accuracy across ages and ethnicities — discuss your result with a healthcare professional.
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Processed locally using client-side JavaScript. Your files and data never touch any server.
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No registration, no waiting queues, and no limits on file conversions or generations.
What is BMI Calculator?
The BMI Calculator converts your height and weight into a Body Mass Index number and places it on the standard WHO scale, from underweight through normal, overweight, and obese. BMI is the same screening metric used by clinics and insurers worldwide: a quick, objective way to track whether your weight sits in a healthy range for your height.
How to use BMI Calculator
Enter your height — in centimeters, or feet and inches.
Enter your weight in kilograms or pounds.
The tool computes BMI = weight (kg) ÷ height (m)² and instantly classifies the result.
Read your category on the WHO scale and track how it moves as your weight changes.
- Uses the official WHO BMI formula and category thresholds
- Metric and imperial units supported with automatic conversion
- Instant classification — underweight, normal, overweight, or obese
- Computed entirely on your device; no height or weight data is sent anywhere
- Checking where your weight falls on the standard scale before or during a fitness program.
- Preparing a screening number for a medical, insurance, or sports-club questionnaire.
- Monitoring a weight-loss or weight-gain goal with a consistent, comparable metric.
Frequently Asked Questions
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