How to Calculate Body Weight Percentage

BMI can help you determine whether you are carrying excess fat.

Body mass index, or BMI, uses your height and weight to estimate your percentage of body fat. Body fat percentages are divided into four categories: underweight, normal, overweight and obese. It is important to aim for a body fat percentage that is normal in order to avoid health conditions such as heart disease and diabetes. BMI is a useful tool when it comes to determining your body fat percentage. However, it may overestimate body fat in a muscular person, and underestimate body fat in those who have lost muscle.

Things You'll Need

• Scale
• Measuring tape
• Note pad

Instructions

Calculating Manually

1. Use the scale to measure your weight. Write your weight on the note pad rounding to the nearest whole number if necessary.

2. Use the measuring tape to measure your height. Write your height on the note pad.

3. Access the BMI Tables. Locate your height in inches in the first column of the table. Mark the location with one finger.

4. Scroll your finger to the right until you locate the number nearest to your weight in pounds. Hold your finger over this spot.

5. Move your finger vertically up the column where your weight is located. Continue scrolling until you reach a number in the second row at the top of the page labeled "BMI." This number represents your body fat percentage.

Using BMI Calculator

1. Use the scale to measure your weight in pounds or kilograms. Write your weight on the note pad rounding to the nearest whole number if necessary.

2. Use the measuring tape to measure your height in feet and inches or centimeters. Write your height on the note pad rounding to the nearest whole number if necessary.

3. Access the BMI Calculator. (see Resource 1) Choose between the standard and metric tables on the calculator.

4. Enter your height and weight in the corresponding fields. Select "compute BMI."

5. Look at the box labeled "your BMI." The number inside represents your body fat percentage. Locate the BMI Category you fall into to determine whether you are in a healthy weight range.

References

• National Heart Lung and Blood Institue: Assessing Your Weight and Health Risk

Resources

• National Heart Lung and Blood Institute: Body Mass Index Table 1
• National Heart Lung and Blood Institute: Body Mass Index Table 2
• National Heart Lung and Blood Institute: Calculate Your Body Mass Index