1. What is a BMI Calculator?

Definition: The Body Mass Index (BMI) is a value derived from an individual's weight and height that provides a simple numeric measure of body fatness.

Purpose: It helps assess whether a person has a healthy body weight for their height.

2. How Does the BMI Calculator Work?

The calculator uses the formula:

Where:

• \( BMI \) — Body Mass Index (kg/m²)
• \( W \) — Weight (kilograms)
• \( H \) — Height (meters)

Explanation: The weight in kilograms is divided by the square of height in meters.

3. BMI Categories

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

4. Using the Calculator

Tips: Enter your weight in kilograms and height in meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI is a useful screening tool but doesn't directly measure body fat. It may overestimate body fat in muscular individuals and underestimate it in older people with less muscle mass.

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

Q3: Can children use this calculator?
A: Children's BMI is interpreted differently using age- and sex-specific percentiles.

Q4: How often should I check my BMI?
A: Periodic checks (every few months) can help track weight changes, but daily measurements aren't useful.

Q5: What if I know my weight in pounds and height in inches?
A: Convert pounds to kg (divide by 2.205) and inches to meters (multiply by 0.0254) before using this calculator.