1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight to screen for weight categories that may lead to health problems. It provides a reliable indicator of body fatness for most people.

2. How is BMI Calculated?

The BMI formula is:

Where:

• \( weight \) — Body weight in kilograms
• \( height \) — Height in meters

Example: For a person weighing 70 kg and 1.75 m tall:
BMI = 70 / (1.75 × 1.75) = 22.9 kg/m²

3. BMI Categories

Standard Categories:

• Underweight: BMI < 18.5
• Normal weight: BMI 18.5-24.9
• Overweight: BMI 25-29.9
• Obese: BMI ≥ 30

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For pounds and inches, first convert to metric units (1 kg = 2.2 lbs, 1 m = 39.37 inches).

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and underestimate it in older people with less muscle mass.

Q2: What is a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy.

Q3: Can children use this calculator?
A: Children need age- and sex-specific BMI percentiles rather than adult categories.

Q4: Why use BMI if it has limitations?
A: BMI remains useful as a simple, quick screening tool for population-level assessment.

Q5: What's better than BMI for measuring health?
A: Waist circumference, body fat percentage, and other measurements combined give a fuller picture.