Content

• To step
• Method 1 of 2: Converting via a simplified procedure
• Method 2 of 2: Converting via a more extensive method
• Tips

There are many tools online for converting inches to centimeters, all of which will tell you that 1 inch equals 2.54 cm. For schoolwork, this information is sometimes not enough, because many teachers expect you to show how you got your answer. Luckily, converting from inches to centimeters is very easy, with a few algebraic steps and getting rid of units properly. If your starting values ​​are in inches, all you have to do is enter your values ​​in the empty space of the simple formula from this article and perform the corresponding calculations. Read on to step 1 below to get started.

To step

Method 1 of 2: Converting via a simplified procedure

1. Write the length in inches. Use a given value for this (as part of a homework assignment, etc.) or measure the length you want to convert with a ruler or tape measure.
2. Multiply the length by 2.54. One inch is roughly equal to 2.54 centimeters, so that means converting inches to centimeters means multiplying an inch by 2.54.
3. Enter the new value in centimeters. Do not forget to add the correct unit to the new value. If you were to do this for school, omitting or misstating the unit could cost you points, or even result in your answer being counted incorrectly.

Method 2 of 2: Converting via a more extensive method

1. Make sure the reading is in inches. This seems logical, but don't forget, especially when it is a mixed value of feet and inches, which are often indicated with quotation marks, such as: 6'2 ". Remember that for such values, the single quotation mark equals the foot, with each foot again containing 12 inches.
   • For example, in the example above from 6'2, we multiply 6 feet by 12 inches / foot to get 72 inches in total. To get this right, we add the extra two inches from our reading to get the final answer 74 inch.
2. Enter the new value (in inches) below in the conversion factor for inches to centimeters.

   ____ in

   *

   2.54 cm       1 in

   =

   ? cm

   This conversion factor will give you an accurate answer in centimeters and is sufficient to show your work if you are a student. Place your value for the number of inches in the blank space at the beginning of the conversion factor and do the calculation.
   • This conversion factor also gives you the correct one units. Note that the "inches" in the denominator of the conversion factor cancel out the "inches" of the value you enter, leaving only "centimeters" in the numerator of your final answer.
   • We now enter 74 inches in the conversion factor.
     • (74 inches × 2.54 centimeters) / (1 inch)
     • (187.96 inch × centimeter) / (1 inch)
     • We eliminate the "inch" because it appears in both the numerator and denominator, giving us the final answer from 187.96 centimeters.
3. Just use a calculator if you don't need to show how you got the answer. If you don't need to show the steps that led to your answer, then to convert from inches to centimeters, you just need to multiply the number of inches by 2.54 using a calculator. This is essentially the same as doing the calculations with the above formula, and it will give you the same number of centimeters.
   • For example, suppose we want to know the value of 6 inches in centimeters, then we do 6 × 2.54 = 15.24 cm.
4. If you want to quickly make this conversion by heart, round off the conversion factor to a simpler value. If you don't have a calculator handy, you can still convert the approximate number of inches to centimeters by using a simpler conversion factor to make mental arithmetic easier. Instead of the more precise 2.54 centimeters / 1 inch conversion factor, use 2.5 centimeters / 1 inch. This will cause your answer to be slightly different, and therefore this method is only suitable for situations where an approximation of the answer is acceptable.
   • For example, we'll convert 31 inches to centimeters with a quick estimate:
     • 2,5 × 30 = 75. 2,5 × 1 = 2,5
     • 75 + 2,5 = 77.5 centimeters.
     • Note that if we had used the more precise 2.54 centimeters / 1 inch conversion factor, our answer 78.74 centimeters would have been. These two answers differ 1.24 centimeters, so about 1.5%.

Tips

• 1 inch = 2.5399999 cm, so 2.54 cm = 1 inch is very accurate based on the following:
  • 1 cm = 0.39370079 inch, which is the same as "1 cm per 0.39370079 inches "(expressed as a ratio), so which is less accurate than that: 4/10 in = 1 cm.