The Ultimate BMI Calculator: Check Your Weight Status Free

BMI Calculator - Check Your Body Mass Index

BMI Calculator

Check Your Body Mass Index Instantly

Calculate Your BMI

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 metres squared.

For most people, BMI is a reliable indicator of body fatness and is used as a screening tool to identify weight categories that may lead to health problems. It's an easy-to-perform and inexpensive method to help health professionals determine who is at greater risk for health issues.

Understanding Your Result

This tool provides a BMI score and a corresponding category. The World Health Organization (WHO) defines the following categories:

BMI Category BMI Range
Underweight Less than 18.5
Normal weight 18.5–24.9
Overweight 25–29.9
Obesity (Class I) 30–34.9
Obesity (Class II) 35–39.9
Obesity (Class III) 40 or more

Health Risks of Being Overweight

Being overweight (BMI 25-29.9) or obese (BMI 30+) increases the risk of developing numerous health problems. The higher your BMI, the greater the risk. These conditions include:

  • Type 2 diabetes
  • High blood pressure (hypertension)
  • Heart disease and stroke
  • Certain types of cancer
  • Sleep apnea and breathing problems
  • Osteoarthritis (joint pain)
  • Gallbladder disease

Health Risks of Being Underweight

Being underweight (BMI less than 18.5) can also pose health risks. A low BMI may be a sign of malnutrition, an underlying medical condition, or an eating disorder. Health risks include:

  • Malnutrition and vitamin deficiencies (e.g., anemia)
  • Weakened immune system
  • Osteoporosis (brittle bones)
  • Fertility issues
  • Developmental problems, especially in children and teens

Limitations of BMI

It's important to remember that BMI is a screening tool, not a diagnostic test. It does not directly measure body fat and can be misleading in some cases. For example, BMI may:

  • Underestimate body fat in older adults or those with low muscle mass.
  • Overestimate body fat in individuals who are very muscular, such as athletes.

Always consult with a healthcare provider for a more complete assessment of your health and any associated risks.

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