BMI Formula:
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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.
The calculator uses the BMI formula:
Where:
Explanation: BMI is calculated by dividing weight in kilograms by the square of height in meters.
Details: BMI is a simple, inexpensive screening tool for weight category—underweight, healthy weight, overweight, and obesity. It helps identify potential weight problems in adults.
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 BMI categories for adults?
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 underestimate it in older people who have lost muscle mass.
Q3: Why use BMI if it has limitations?
A: Despite limitations, BMI is a useful population-level measure of overweight and obesity.
Q4: Should children use this calculator?
A: No, children and teens need age- and sex-specific percentiles rather than the adult categories.
Q5: What's next after calculating BMI?
A: Consult a healthcare provider for further assessment if BMI indicates overweight or obesity.