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Adult BMI Calculation Formula

BMI Formula:

\[ BMI = \frac{weight}{height^2} \]

kg
meters

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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. BMI screens for weight categories that may lead to health problems.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

\[ BMI = \frac{weight}{height^2} \]

Where:

Explanation: 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.

3. Importance of BMI Calculation

Details: BMI is a screening tool to identify possible weight problems in adults. It may indicate whether you are underweight, normal weight, overweight, or obese, which can have implications for your health.

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 underestimate it in older people who have lost muscle mass.

Q3: Why use metric units?
A: The standard formula uses kg and m. For imperial units, the formula is [weight (lb) / height² (in)] × 703.

Q4: Should children use this calculator?
A: No, children and teens need age- and sex-specific percentile BMI calculations.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but consult your doctor for individual assessment.

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