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BMI Calculator

Updated for 2026

Quick Answer

Calculate your Body Mass Index (BMI) to understand your body fat based on height and weight. Toggle between metric (kg/cm) and imperial (lbs/ft) units. Use typical values to get quick results.

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BMI Calculator

Last updated: March 26, 2026

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is used to screen for weight categories that may lead to health problems.

Medical Disclaimer: This calculator is for informational purposes only and is not intended as medical advice. BMI does not account for muscle mass, bone density, or fat distribution. Please consult a healthcare professional for a complete health assessment.

How is BMI Calculated?

The BMI is defined as the body mass divided by the square of the body height, and is universally expressed in units of kg/m2kg/m^2.

The Standard Metric Formula

BMI=weight in kg(height in m)2\text{BMI} = \frac{\text{weight in kg}}{(\text{height in m})^2}

BMI Categories

According to the World Health Organization (WHO), BMI is categorized as follows:

  • Underweight: Less than 18.5
  • Normal weight: 18.5 – 24.9
  • Overweight: 25.0 – 29.9
  • Obese: 30.0 or higher

Frequently Asked Questions

Is BMI accurate for everyone?

No. Because BMI only relies on height and weight, it does not distinguish between muscle and fat. Highly muscular athletes may have a high BMI but very little body fat. Conversely, older adults might be in the "normal" range but have high body fat and low muscle mass.

How can I lower my BMI?

Lowering your BMI requires creating a calorie deficit. This is achieved by consuming fewer calories than your body burns through a combination of dietary changes and increased physical activity.

Does BMI differ for men and women?

The standard adult BMI calculation is identical for both men and women. However, women naturally tend to have higher body fat percentages than men at the same BMI.