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The Body Mass Index (BMI) Calculator is a versatile tool to assess an individual's body weight relative to their height. This measurement is widely used as a general indicator of whether a person has a healthy body weight for their height.

⚖️ How It Works

To calculate BMI, you need to provide:

• Unit System: Choose Metric (cm, kg) or Imperial (ft, in, lbs).
• Age: Your age in years (for context, as interpretation can vary).
• Gender: Male or Female.
• Height & Weight: Based on your selected unit system.

The calculator uses standard formulas:

• Metric Formula: BMI = weight (kg) / (height (m))²
• Imperial Formula: BMI = (weight (lb) / (height (in))²) × 703

📊 WHO BMI Interpretation & Categories (Adults 20+)

For adults, the BMI categories established by the World Health Organization (WHO) are as follows:

Frequently Asked Questions (FAQ)

What is Body Mass Index (BMI)?

BMI is a numerical value of your weight in relation to your height. It's a simple, inexpensive screening method for weight categories—underweight, healthy weight, overweight, and obesity—that may lead to health problems.

Is BMI accurate for athletes or bodybuilders?

Not always. BMI does not distinguish between fat and muscle mass. Since muscle is denser than fat, very muscular individuals like athletes may have a high BMI that incorrectly categorizes them as overweight or obese, even though their body fat is low.

How is BMI interpreted for children and teens?

For individuals under 20, BMI is interpreted differently. It's plotted on age- and sex-specific percentile charts. A BMI in the 85th percentile, for example, means the child's weight is higher than that of 85% of other children of the same age and sex. This calculator provides a simplified category for children, but a healthcare provider should be consulted for an accurate assessment using official growth charts.

What are the limitations of BMI?

Besides not accounting for body composition, BMI also doesn't consider factors like body frame size, age-related muscle loss, or fat distribution. Therefore, it should be used as a general screening tool, not a diagnostic one. Our Ideal Weight Calculator provides alternative perspectives.

If my BMI is high, what should I do?

A high BMI is an indicator of potential health risks, but it is not a diagnosis. It's best to consult with a healthcare professional who can perform a more comprehensive assessment, including measuring body fat percentage and discussing your lifestyle and family history.