BMI Calculator
Enter your weight and height to calculate your Body Mass Index (BMI). Supports both metric (kg/cm) and imperial (lbs/ft+in) units, and shows your weight category with color-coded results.
How to Use
Metric Calculation
Enter 70 kg and 175 cm to get a BMI of 22.9, which falls in the Normal category.
Imperial Calculation
Switch to lbs and ft/in, then enter 154 lbs, 5 ft 9 in to get the same BMI of approximately 22.7.
Check Different Categories
Try various weight and height combinations to understand the boundaries between Underweight, Normal, Overweight, and Obese categories.
How It Works
What Is BMI?
Body Mass Index (BMI) is a simple measure that uses your height and weight to estimate whether you are underweight, at a healthy weight, overweight, or obese. It is calculated by dividing your weight in kilograms by the square of your height in meters: BMI = kg / m².
BMI Categories
The World Health Organization defines four main categories: Underweight (BMI below 18.5), Normal weight (18.5 to 24.9), Overweight (25 to 29.9), and Obese (30 and above). While BMI is a useful screening tool, it does not directly measure body fat and may not be accurate for athletes or older adults.
Frequently Asked Questions
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