BMI Calculator

Calculate your Body Mass Index and understand what it means for your health

BMI Calculator

Calculate your Body Mass Index and health status

About BMI Calculator

Our free BMI calculator helps you determine your Body Mass Index (BMI) and understand what it means for your health. BMI is a simple measure that uses your height and weight to work out if your weight is healthy.

What is BMI?

Body Mass Index (BMI) is a number calculated from your weight and height. It provides a reliable indicator of body fatness for most people and is used to screen for weight categories that may lead to health problems.

BMI Categories

  • Underweight: BMI less than 18.5
  • Normal weight: BMI 18.5 to 24.9
  • Overweight: BMI 25 to 29.9
  • Obese Class I: BMI 30 to 34.9
  • Obese Class II: BMI 35 to 39.9
  • Obese Class III: BMI 40 or greater

Features

  • Multiple unit support (lbs/kg, ft/in/cm)
  • Instant BMI calculation and categorization
  • Health risk assessment
  • Ideal weight range calculation
  • Mobile-friendly design

Important Note

While BMI is a useful screening tool, it doesn't measure body fat directly or account for factors like muscle mass, bone density, age, sex, and ethnicity. For a complete health assessment, consult with a healthcare professional.

About Body Mass Index (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 Categories:

  • Underweight: BMI less than 18.5
  • Normal weight: BMI 18.5 to 24.9
  • Overweight: BMI 25 to 29.9
  • Obese: BMI 30 or greater

BMI Formula:

BMI = Weight (kg) ÷ Height (m)²

Important Considerations:

  • BMI doesn't distinguish between muscle and fat mass
  • Athletes may have high BMI due to muscle mass
  • Elderly people may have low BMI due to muscle loss
  • BMI ranges may vary by ethnicity
  • Not suitable for children and adolescents

When to Use BMI:

  • General health screening and population studies
  • Initial assessment of weight status
  • Tracking weight changes over time
  • Discussing weight with healthcare providers
  • Setting general health and fitness goals