# How to Calculate BMI – The BMI Formula

## BMI : Body Mass Index

Body Mass Index is defined as your weight divided by the square of your height, using the metric units kg/m^2.

The BMI formula does not apply to children (see the references below). You can calculate BMI using one of these BMI formulas:

• Metric Units: BMI = Weight[kg] / ( Height[m] x Height[m] )
• English Units: BMI = 703 x Weight[lb] / ( Height[in] x Height[in] )

## BMI Chart and Calculator

This spreadsheet for Excel contains a BMI calculator that uses both the CDC and the NHANES II definitions for BMI. The chart shows your BMI on the spectrum based on the chosen formula and gender. This spreadsheet also contains a worksheet used to create the BMI charts listed above (using quite a few special tricks that may delight the Excel enthusiast).

Technically, both the CDC and NHANES II definitions use the same BMI formula. It’s only the range of values for each category that is different.

There are other formulas besides the BMI that are used for determining ideal weight. Our Ideal Weight Chart includes some additional formulas, but keep in mind that “ideal” weight can be highly subjective, and formulas are usually just approximations.

Also, check out our Weight Loss Charts.