BMI Calculator Online
Calculate your Body Mass Index instantly with metric or imperial units.
BMI Scale
Your BMI
24.2
All calculations happen in your browser. No data stored.
What Is BMI?
BMI Calculator is a free online tool that calculate your Body Mass Index instantly with metric or imperial units. No files are uploaded — everything is processed locally on your device.
This BMI calculator computes your Body Mass Index from your weight and height, providing a general indication of whether your body weight falls within a healthy range. The formula divides weight in kilograms by height in meters squared. While BMI does not directly measure body fat, it is a widely used screening tool in healthcare for identifying potential weight-related health risks. Our calculator supports both metric and imperial units and runs entirely in your browser.
Privacy guarantee: BMI Calculator processes all files directly in your browser using WebAssembly. No data is uploaded to any server, no information is collected, and the tool works offline after loading. Unlimited usage with no signup, no watermarks, and no file size limits.
How to Use BMI Calculator
Select your unit system
Choose between metric (kg/cm) or imperial (lbs/ft-in) measurements.
Enter your measurements
Input your weight and height in the selected unit system.
Check your BMI result
See your BMI value, weight category, and where you fall on the BMI scale.
Why Use Our BMI Calculator?
Frequently Asked Questions
What are the BMI categories for adults?
Underweight is below 18.5, normal weight is 18.5-24.9, overweight is 25.0-29.9, and obese is 30.0 and above. These ranges are defined by the World Health Organization.
Is BMI an accurate measure of body fat?
BMI is a screening tool, not a diagnostic one. It does not distinguish between muscle and fat mass, so athletes with high muscle mass may show a high BMI despite having low body fat.
Does BMI apply the same way to all ages?
BMI categories listed here apply to adults aged 20 and over. For children and teens, BMI is interpreted using age- and sex-specific percentile charts.
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