BMI Calculator

BMI Calculator


BMI Category Range
Underweight <18.5
Normal weight 18.5–24.9
Overweight 25–29.9
Obesity BMI of 30 or greater

What is BMI Calculator?

BMI Calculator (Body Mass Index Calculator) is a free tool for numerical measures of a person's body weight concerning their height. BMI is a widely used screening tool to identify possible weight-related health problems. It helps to categorize individuals into different weight status categories, such as underweight, normal weight, overweight, and obesity. The formula for calculating BMI is as follows:

BMI= Weight (kg)/Height (ft)

Alternatively, if you measure weight in pounds and height in inches, you can use the following formula:

BMI= Weight in pound/Height in inches X 703

Here is a general guide to interpreting BMI results for adults:

  • Underweight: BMI less than 18.5
  • Normal weight: BMI between 18.5 and 24.9
  • Overweight: BMI between 25 and 29.9
  • Obesity: BMI of 30 or greater
    • Class 1 Obesity: BMI less than 34.9
    • Class 2 Obesity: BMI between 35 and 39.9
    • Class 3 Obesity: BMI above 40

Why BMI is important?

  1. BMI provides a simple and widely used method to assess an individual's overall body weight concerning height.
  2. It serves as a screening tool for identifying potential weight-related health risks.
  3. BMI is valuable for assessing and monitoring population-level trends in obesity and overweight.
  4. It helps healthcare professionals in making initial assessments of an individual's risk for various health conditions associated with weight.
  5. BMI is a cost-effective and easily accessible tool for assessing body composition on a large scale.
  6. It assists in identifying individuals who may be at risk for conditions such as type 2 diabetes, heart disease, and certain cancers.
  7. BMI can be used in clinical settings to guide discussions about weight management and lifestyle changes.
  8. It provides a standardized measure that allows for comparisons across different populations and demographic groups.
  9. BMI is a useful metric in epidemiological research to study the prevalence of obesity and its impact on health outcomes.
  10. Monitoring changes in BMI over time can help individuals and healthcare providers track the effectiveness of weight management interventions.