BMI Formula:
From: | To: |
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.
The calculator uses the standard BMI formula:
Where:
Explanation: The formula calculates body mass per unit of height squared, providing a standardized measure of body composition.
Details: BMI provides a simple numeric measure of a person's body fat based on height and weight that applies to most adults. It is used to screen for weight categories that may lead to health problems.
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).
Q1: What are the standard BMI categories?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obese (≥30).
Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in muscular individuals and underestimate it in older people who have lost muscle mass.
Q3: Should BMI be interpreted the same for all ages?
A: This calculator is for adults (20+ years). Children and teens need age- and sex-specific percentiles.
Q4: What are the limitations of BMI?
A: BMI doesn't account for muscle mass, bone density, overall body composition, or racial/ethnic differences.
Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but individual factors should be considered.