How to Determine Your Body Mass Index

Body mass index (BMI) is often used to determine whether a person is at risk for weight-related health problems. It is one of many ways to determine your ideal weight.

Difficulty:

Moderately Easy

Instructions

Things You'll Need

• Weight Charts
• Calculators
• Measuring Tapes
• Scales
• Pencils
• Spiral Notebooks

1. Grab a calculator, pencil and piece of paper.

2. Understand that the formula for BMI = weight ÷ (height x height). Weight is represented in kilograms; height is represented in meters.

3. Determine your weight in kilograms. To do this, divide your weight (in pounds) by 2.2. For example, 150 lbs ÷ 2.2 = 68.2 kilograms. Write this number on your paper.

4. Determine your height in meters by dividing your height (in inches) by 39.37. Know that there are 12 inches in 1 foot. For example, 64 inches ÷ 39.37 = 1.626 meters.

5. Square your height in meters. In other words, multiply your height times itself. For example: 1.626 meters x 1.626 meters = 2.644 meters. Write this number on your piece of paper.

6. Divide your answer from number 3 by your answer for number 6. In this example, 68.2 kilograms ÷ 2.644 meters = 25.79. This number represents your BMI.

Tips & Warnings

• In general, a BMI of 20-25 is considered ideal. A BMI over 30 is considered obese.

• BMI is just one way of determining whether you are at risk for weight-related health problems. There are many other factors a health or fitness professional can evaluate for you.

• It is highly recommended that you have your percentage of body fat measured by a health or fitness professional. There are several methods to determine body fat percentage, including calipers, bioelectrical impedance and underwater weighing.

• Check with your health care provider before beginning a weight-loss program.

Resources

• Body Mass Index Online Calculator