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
• \( height \) — Height in meters

Categories:

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

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 more objectively with their patients. It is used to screen for weight categories that may lead to health problems.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. All values must be valid (weight > 0, height > 0). For height in centimeters, divide by 100 to convert to meters.

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI may not be accurate for athletes (who may have high muscle mass), pregnant women, children, or the elderly. Other measurements like waist circumference may provide additional information.

Q2: What is a healthy BMI range?
A: For most adults, a healthy BMI is between 18.5 and 24.9. However, optimal BMI may vary by age, sex, and ethnicity.

Q3: How often should I check my BMI?
A: Periodic checks (e.g., every 6-12 months) are sufficient for most adults unless you're actively trying to change your weight.

Q4: Does BMI measure body fat?
A: BMI is a surrogate measure of body fatness but doesn't directly measure body fat. Other methods like skinfold thickness measurements or bioelectrical impedance may be more accurate.

Q5: Should children use the same BMI categories?
A: No, children's BMI is interpreted differently using age- and sex-specific percentiles rather than fixed categories.