What are the BMI categories?

The standard BMI categories for adults are: Underweight (BMI below 18.5), Normal weight (18.5–24.9), Overweight (25.0–29.9), and Obese (30.0 and above). These thresholds may vary slightly by age, sex, and ethnicity. For children and teens, BMI is interpreted using age- and sex-specific percentiles.

What are the limitations of BMI?

BMI does not directly measure body fat. It can misclassify people with high muscle mass as overweight (e.g., athletes), and it doesn't account for fat distribution, bone density, or age-related changes. It is also less accurate for very tall or very short individuals. Always consult a healthcare professional for a comprehensive health evaluation.

What is a healthy BMI for adults?

A BMI between 18.5 and 24.9 is considered healthy for most adults. To stay in this range, you can calculate your healthy weight range: multiply your height in meters squared by 18.5 (lower bound) and 24.9 (upper bound). For example, a person 1.70 m tall should weigh between 53.5 kg and 71.9 kg for a healthy BMI.

Does BMI differ for men and women?

The BMI formula is the same for both men and women, but the meaning can differ. Women naturally have more body fat than men at the same BMI. Some health professionals use different reference ranges or supplement BMI with other measurements like waist circumference for a more accurate health assessment.

Body Mass Index (BMI) Calculator

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BMI Calculator

Calculate your Body Mass Index (BMI) to assess your weight relative to your height. Enter your height and weight to get your BMI and weight category instantly.

Unit System

Age

Gender

Height

Weight

Frequently Asked Questions

BMI (Body Mass Index) is a numerical value derived from your weight and height. The formula is: BMI = weight (kg) / height² (m). For example, a person who is 70 kg and 1.75 m tall has a BMI of 22.9. In imperial units: BMI = (weight in lbs × 703) / height² (inches). It provides a simple way to classify weight categories.

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