Aside from infancy, Americans normally reference human height in feet and inches. Even in some countries where the metric system is the officially adopted system of measurement, such as Canada, the foot-inch model is more common than centimeters. To convert from the typical foot-inch model to just inches, first establish a common unit, in this case inches. The conversion factor for feet to inches is 12 because there are 12 inches in a foot.
Record the height you need to convert on a piece of paper. For example, 5 feet 9 inches.
Calculate the total number of inches in just the feet portion of your measurement. For example, the equation to convert 5 feet to inches is 5 x 12 = 60. Therefore, there are 60 inches in 5 feet.
Add the number of inches in your original height measurement to the number of inches from Step 2. For example: 5 feet 9 inches = 60 + 9 = 69 inches.