1. What is BMI?

Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity in adults. It is defined as the weight in kilograms divided by the square of the height in meters.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

• \( weight \) — Body weight in kilograms (kg)
• \( height \) — Height in feet (ft)
• \( 0.3048 \) — Conversion factor from feet to meters

Explanation: The formula converts height from feet to meters (by multiplying by 0.3048) then calculates the standard BMI using weight in kg and height in meters.

3. Importance of BMI Calculation

Details: BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems objectively with their patients.

4. Using the Calculator

Tips: Enter weight in kilograms and height in feet. All values must be valid (weight > 0, height > 0). For accurate results, measure weight without heavy clothing and height without shoes.

5. Frequently Asked Questions (FAQ)

Q1: What are the standard BMI categories?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obesity (≥30).

Q2: Are there limitations to BMI?
A: BMI doesn't distinguish between muscle and fat, so athletes may have high BMI without excess fat. It also doesn't account for fat distribution.

Q3: Is BMI different for children?
A: Yes, children's BMI is age and sex-specific and is interpreted using percentile charts rather than fixed categories.

Q4: How often should I check my BMI?
A: For most adults, checking every few months is sufficient unless you're actively trying to lose or gain weight.

Q5: Should I use this if I'm pregnant?
A: BMI calculations during pregnancy are not meaningful as weight gain is expected and necessary for healthy fetal development.