BMI Formula - How do you calculate your BMI?
Body Mass Index 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. A BMI of 25.0 or more is overweight, while the healthy range is 18.5 to 24.9. BMI applies to most adults 18-65 years.
So, what units are used to measure BMI?
Body mass index (BMI) is obtained by measuring a subject's weight in kilograms (kg) or pounds (lb) and the subject's height in meters (m) or inches (in). The BMI is then calculated by dividing the subject's weight by the square of his/her height. Therefore, weight is normalized for height.
BMI Formula by Adolphe Quetelet |
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It was developed by Belgium
Statistician Adolphe Quetelet approximately 150 years ago. This was
before the era of electronic calculators; any formula used to indicate
weight status needed to be easy for physicians to manually calculate.
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Adolphe Quetelet: Creator Of The BMI Formula |
How To Calculate BMI |
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Metric Method |
Imperial (US) Method |
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Bmi Calculator Formula
BMI Formula
Body Mass Index, or BMI, indicates how much weight a person has in relation to their height. This test may be used to determine whether a person is underweight, normal weight, overweight, or obese in general. No matter what units are used for the calculation of the BMI, the formula remains the same, although the units themselves differ according to whether the metric system or the imperial system is employed.
The kilogram (kg) is used to measure weight, while the meter (m) is used to measure height in the metric method. The formula for calculating BMI using the metric system is as follows:
BMI = weight (kg) / height² (m²)
When calculating the BMI using the metric method, you must square your height in meters and then divide your weight in kilograms by the squared height.
Imperial measurements use pounds (lb) to measure weight and inches (in) to measure height. A slight difference exists in the formula for calculating BMI when using the imperial system:
BMI = (weight (lb) / height² (in²)) * 703
The height in inches is squared, and then the weight is divided by the squared height, and the result is multiplied by 703.
The formula produces a number representing BMI, no matter what method is used. An overweight person with a BMI of over 25.0 is overweight; healthy people have a BMI between 18.5 and 24.9. Note that BMI is only used for screening purposes and does not measure percentages of body fat.
BMI refers to the body mass index of an individual between the ages of 18 and 65. Because muscle weighs more than fat, it may not provide an accurate assessment for athletes or individuals with a high muscle mass. Depending on the circumstances, additional factors may need to be considered to evaluate a person's overall health.