BMI Calculator

About BMI Calculator

Explanation: The Body Mass Index (BMI) calculator helps you estimate whether your weight falls within a healthy range for your height. BMI is a widely used metric to assess whether a person is underweight, normal weight, overweight, or obese, based on their height and weight. It’s a quick screening tool but doesn’t directly measure body fat.

Mathematical Formula:

  • Metric System:
    BMI formula for Metric System
  • Imperial System:
    BMI formula for Imperial System

How It Works:

1. Metric System: For measurements in kilograms and meters, divide the weight by the square of the height.
Example: If someone weighs 70 kg and is 1.75 m tall, their BMI is calculated as 701.752=22.86\frac{70}{1.75^2} = 22.861.75270=22.86, which falls within the normal range.

2. Imperial System: When using pounds and inches, multiply the weight by 703, then divide by the square of the height in inches.
Example: If a person weighs 154 lbs and is 68 inches tall, their BMI is:
BMI Imperial Calculation Example

Understanding BMI Categories:

  • Underweight: BMI less than 18.5
  • Normal weight: BMI 18.5–24.9
  • Overweight: BMI 25–29.9
  • Obesity: BMI 30 or higher

Limitations:

While BMI is a useful screening tool, it doesn’t consider muscle mass, bone density, or fat distribution. For athletes or muscular individuals, BMI may classify them as overweight or obese even though their body fat is low. Always consult a healthcare provider for a comprehensive health assessment.