From age 20 years onwards, the same BMI calculations are used for both men and women, which is based on your weight (in kg or pound) and your height (in meters or inches) and is universally expressed as kg/ m. It provides a simple calculation to measure your body fat to determine whether your body weight can be considered healthy. Using an online BMI calculator, you just have to put in your weight and height to know your BMI. But if you wish to calculate your BMI on your own, then you can use the following formula;
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Formula with metric units
BMI = weight (kg) / {height ( m)} 2
Formula with imperial units
BMI = 703 x weight (lbs.)/ {height (in)} 2