How to Calculate Your Weight Based on Height and Age

Even though weight sits on us all differently, there is a way to calculate what your ideal weight should be. Using your height, age, and weight, you can calculate this number, usually called the body mass index (BMI).

Things You'll Need

• Calculator Tape measure Scale A BMI chart

Instructions

Calculating BMI

1. Measure yourself and note the height in inches. For example, if you are 5'10", then in total you are 70 inches.

2. 

   Square your height; that is, multiply the number of inches of your height by itself. Using the previous example of 70 inches, that would mean that you multiply 70 by 70 to get a result of 4,900.

3. Divide your weight in pounds by the squared number you just came up with. Keeping along with our example, if the 5'10" person is 160, they will divide 160 by 4,900.

4. For North Americans working with pounds and inches, multiply the number you got from dividing your weight by your squared height by 703 to get your BMI number. U.K. residents should multiply by 6.35 instead of 703. If you are using the metric system, you may skip this step.

5. Look up your BMI number on the BMI chart. Some charts will incorporate age into the chart while others do not. BMI charts are easily found on the internet by searching for the keywords "BMI chart."

Tips & Warnings

• BMI charts vary by region and ethnicity, so it is important to make sure you have the correct one.

References

• Better Ideal Weight Body Calculations

Resources

• Read this Article in Spanish
• Girls BMI Chart with Age Variable
• Basic BMI Chart