1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. It provides a reliable indicator of body fatness for most people.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

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

Explanation: The BMI calculation divides an adult's weight in kilograms by their height in meters squared.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive screening method for weight category—underweight, healthy weight, overweight, and obesity. It can help identify potential weight problems in adults.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. All values must be valid (weight > 0, height > 0). For pounds and inches, convert first (1 kg = 2.2 lbs, 1 m = 39.37 inches).

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: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and those with muscular builds. It may underestimate body fat in older persons and those who have lost muscle.

Q3: How often should I check my BMI?
A: For most adults, checking BMI once a year is sufficient unless you're actively trying to lose or gain weight.

Q4: Can children use this calculator?
A: Children's BMI is calculated differently, using percentiles based on age and sex.

Q5: What's the Python formula for BMI?
A: bmi = weight / (height ** 2) where weight is in kg and height is in meters.