Body Mass Index Calculator

What is BMI?

The "Body Mass Index", or BMI, is a measurement of body fat calculated from an adult's weight and height.

BMI does not measure body fat directly, but it’s a reliable indicator of body fatness for most people.

For a given height, BMI is proportional to mass. However, for a given mass, BMI is inversely proportional to the square of the height. It’s an alternative for direct measures of body fat and is an inexpensive method of screening for weight categories that may lead to health problems.

The correlation between the BMI score and body fatness is fairly strong. It works for adults, both men and women above age 18, and it’s a good indicator of the amount of body fat you have, which is directly related to the risk of various diseases and early death. However the correlation varies by sex, age and race. Examples:

  • Women tend to have more body fat than men.
  • Older people tend to have more body fat than younger adults.
  • Highly trained athletes may have a high BMI because of increased muscularity rather than increased body fatness.

BMI provides a simple numeric measure of an adult’s thickness or thinness, allowing health professionals to discuss overweight and underweight problems more objectively with their patients.

Your BMI score

Your body mass index is a measurement which determines which weight category you belong to, and it will give you an idea of how your weight compares to common values.

Your BMI score can be used to indicate if you are underweight (<18.5), normal (18.5 - 24.9), overweight (25.0 – 29.9) or obese (>30). So depending on your height and weight, you can belong to one of the following weight categories:

< BMI 18.5
18.5 - 24.9
25 - 29.9
> BMI 30

The BMI ranges are based on the relationship between body weight, diseases and death. Overweight and obese adults are at increased risk for many diseases and health conditions, including:

Hypertension Stroke
Dyslipidemia Gallbladder disease
Diabetes (type 2) Osteoarthritis
Coronary heart disease Sleep apnea
Respiratory problems Some cancers (breast, colon and endometrial)

It’s also important to remember that BMI is only one factor related to risk of disease.

For assessing someone’s likelihood of developing overweight related diseases we recommend looking at two other predictors: the waist circumference and other risk factors such as high blood pressure or physical inactivity.

BMI Chart

BMI can also be calculated from a chart which displays BMI as a function of mass and height.

The following BMI charts shows examples of body mass indexes, the figure at which your height corresponds with your weight is your body mass index. Find yours here:

Women

BMI Women

BMI chart for women

(18 - 65 years old)

Men

BMI Men

BMI chart for men

(18 - 65 years old)

Children

BMI Children

BMI chart for childrens

(2 through 18 years old)

Calculate your BMI

How can you calculate your BMI? The formula is easy to compute. In fact, the simplicity of the BMI formula is part of the reason for its success. Calculate your BMI automatically here and find your weight category using our BMI calculator.

Popular BMI scores

After using our BMI calculator you can check your BMI score here:

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