BMI Calculator

The Body Mass Index (BMI)

Body mass index (BMI) is a measure of body fat based on height and weight that is used to determine whether a person is underweight, normal weight, overweight, or obese. It is calculated by dividing a person`s weight in kilograms by the square of their height in meters.

BMI is generally used as a population-level tool, rather than for individual assessment, and it has some limitations. It does not take into account differences in muscle mass, bone density, and distribution of fat, and it may not be accurate for athletes or older people who have lost muscle mass. However, it is a simple and widely used tool that can provide a rough estimate of a person`s body fat and can be used to determine if a person is at an unhealthy weight.

The World Health Organization (WHO) classifies BMI into the following categories:

  • Underweight: BMI less than 18.5
  • Normal weight: BMI between 18.5 and 24.9
  • Overweight: BMI between 25 and 29.9
  • Obese: BMI 30 or higher

How to calculate BMI?

You can use the following calculation to determine your BMI:

BMI = weight (kg) / height (m)^2

For example, if you weigh 70 kilograms and are 1.75 meters tall, your BMI would be 70 / (1.75)^2 = 22.86.

You can also use an online calculator or a smartphone app to determine your BMI. Just enter your weight and height, and the calculator will do the rest.

It`s important to note that BMI is only a rough estimate of body fat, and it may not be accurate for everyone. It is not a diagnostic tool and should not be used as the sole basis for making decisions about your health. Other factors, such as muscle mass, bone density, and distribution of fat, can also affect your weight and health. If you have concerns about your weight or overall health, it`s best to speak with a healthcare professional.

Frequently Asked Questions

    1. weight (kg) / [height (m)]2 or [weight (kg) / height (cm) / height (cm)] x 10,000
    2. Example: When your weight is 55kg and height is 155cm, what will be your BMI?
    3. (55kg / 155cm / 155cm ) x 10,000 = 22.9 kg/m2
    • Underweight - BMI less than 18.5kg/m2 (BMI =< 18.5kg/m2)
    • Normal weight - BMI between 18.5kg/m2 and 24kg/m2 (18.5kg/m2 - 24.9kg/m2)
    • Overweight - BMI between 25kg/m2 and 29.9kg/m2 (25kg/m2 - 29.9kg/m2)
    • Obesity - BMI above 30kg/m2 (BMI > 30kg/m2)
  • For calculating BMI, you can choose the height in cm and weight in kg and the result will be kg/m2.

  • Numerous demographic and social factors are connected to weight. According to research, BMI rises with age.