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The Ultimate Guide to Calculating BMI and Maintaining Health

Learn what Body Mass Index really tells you about your health, its limitations, and how to use our calculator effectively.

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BMI Calculator

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What is Body Mass Index?

Body Mass Index (BMI) is a person's weight in kilograms divided by the square of height in meters. It is an inexpensive and easy screening method for weight category—underweight, healthy weight, overweight, and obesity.

The Standard Categories

  • Underweight: BMI is less than 18.5
  • Normal weight: BMI is 18.5 to 24.9
  • Overweight: BMI is 25 to 29.9
  • Obesity: BMI is 30 or more

Limitations of BMI

While useful, BMI does not measure body fat directly. For example, athletes with high muscle mass may have a high BMI but low body fat. Always consult with a healthcare provider for a complete assessment.

How To Use The Tool In 3 Steps

  1. 1Open BMI Calculator and enter your required inputs.
  2. 2Review the generated output and adjust values to compare scenarios.
  3. 3Copy or save the result for your final decision or workflow.

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