The body mass index (BMI) is used to determine a person's body fat. While the BMI may have shortcomings--for example, it fails to distinguish the weight of muscle from fat--it is frequently used to evaluate one's health. BMIs are also a useful tool to determine who can benefit from weight loss. A BMI is calculated using height and weight. With some basic information and simple math, a woman can easily figure out her BMI.

### Things You'll Need

- Scale
- Measuring tape or ruler

- Calculator or paper and pencil

Weigh yourself on a scale and write down the number.

Measure your height. Note the unit of measurement, whether in feet and inches or meters.

Calculate your BMI using the standard formula: Divide your weight, in pounds or kilograms, by height squared, in inches or meters, and multiply by a conversion factor of 703. For example, a female who weighs 130 pounds and is 5 feet 4 inches tall would divide 130 by 64 squared. The result would be multiplied by 703, giving her a BMI of 22.31.