How To Convert Inches To Cm

Have you ever wondered – how many centimeters in an inch? And what is the formula to convert inches to centimeters? Well, we all do and if you’re here and reading this – then I know what you’re thinking: Is there a simple way to calculate inches to centimeters and convert between these units? I’m here to answer exactly that!

There are many tools for converting inches to centimeters on the web, all of which will tell you that 1 inch = 2.54 cm. However, in academic situations, this information is sometimes insufficient, as many teachers will require you to show your work. Luckily, converting inches to centimeters using algebraic steps and proper unit cancellation is a fairly simple task. If your initial measurements are in inches, the process is as simple as plugging your values into the blank space in the simple formula provided in this article and following the calculations. See Step 1 below to get started.

Method 1Method 1 of 2:Converting via Simplified Process

1. 1Write your length value in inches. Either use the value you have been given (as part of a homework problem, etc.) or use a ruler or tape measure to measure the length you wish to convert.
2. 2Multiply your length value by 2.54. One inch is equal to roughly 2.54 centimeters, so converting inches to centimeters means multiplying a value in inches by 2.54.
3. 3Label your new value as centimeters. Don’t forget to include the correct label on your new value. If you’re doing schoolwork, using the wrong label can result in points deducted form your answer or even your answer being marked as wrong.

Method 2Method 2 of 2:Converting via Detailed Process

1. 1Ensure your measurement is in inches. This may seem like a no-brainer, but it’s important to remember, especially when dealing with mixed measurements of feet and inches, which are often denoted by apostrophe markings, like this: 6’2″. Remember that in such measurements the number marked by the single apostrophe is feet, each of which contains 12 inches.
   • For example, in the example above, 6’2″, we would multiply 6 feet by 12 inches/foot to get 72 inches total. To this we’ll add the extra two inches from our measurement to get a final value of 74 inches.
2. 2Insert your value (in inches) into the inches to centimeters conversion factor below.____ in*  2.54 cm  
         1 in= ? cmThis conversion factor will get you an accurate answer in centimeters and satisfy most “show your work” requirements, if you’re a student. Simply place your value for inches into the blank at the beginning of the conversion factor and multiply through.
   • This conversion factor will also get you the correct units. Note that the “inches” label in the denominator of the conversion factor cancels with the “inches” label of the value you plug in, leaving only the “centimeters” label in the numerator of the conversion factor for your final answer.
   • Let’s try plugging our example of 74 inches into the conversion factor.
     • (74 inches × 2.54 centimeters)/(1 inch)
     • (187.96 inches × centimeters)/(1 inch)
     • We cancel the “inch” labels because they appear once in both the numerator and the denominator, leaving us with a final answer of 187.96 centimeters.
3. 3Simply use a calculator if you don’t need to show your work. If you’re not interested in showing your work for academic purposes, all you need to do to convert inches to centimeters is multiply your inches value by 2.54 on a calculator. This is essentially the same as performing the calculations in the formula above, and will get you the same result in centimeters.
   • For example, if we want to know the value of 6 inches in centimeters, we would just multiply 6 × 2.54 = 15.24 cm.
4. 4For on-the-fly mental calculations, round your conversion factor to an easier value. If you don’t have a calculator handy, it’s still possible to approximate an inches-to-centimeters conversion by using a “rounder” conversion factor to make mental multiplication easier. Instead of using the precise conversion factor of 2.54 centimeters/1 inch, use 2.5 centimeters/1 inch. Note that this will cause your final answer to be slightly inaccurate, so this method is only suitable for situations in which loose estimations are acceptable.
   • For instance, let’s convert 31 inches to centimeters using this quick estimation method:
     • 2.5 × 30 = 75. 2.5 × 1 = 2.5
     • 75 + 2.5 = 77.5 centimeters.
     • Note that if we had used the precise conversion factor of 2.54 centimeters/1 inch, our answer would have been 78.74 centimeters. These two answers differ by 1.24 centimeters, or about 1.5%.

Inch

Definition: An inch (symbol: in) is a unit of length in the imperial and US customary systems of measurement. An inch was defined to be equivalent to exactly 25.4 millimeters in 1959. There are 12 inches in a foot and 36 inches in a yard.

History/origin: The term “inch” was derived from the Latin unit “uncia” which equated to “one-twelfth” of a Roman foot.

There have been a number of different standards for the inch in the past, with the current definition being based on the international yard. One of the earliest definitions of the inch was based on barleycorns, where an inch was equal to the length of three grains of dry, round barley placed end-to-end. Another version of the inch is also believed to have been derived from the width of a human thumb, where the length was obtained from averaging the width of three thumbs: a small, a medium, and a large one.

Current use: The inch is mostly used in the United States, Canada, and the United Kingdom. It is also sometimes used in Japan (as well as other countries) in relation to electronic parts, like the size of display screens.

Centimeter

Definition: A centimeter (symbol: cm) is a unit of length in the International System of Units (SI), the current form of the metric system. It is defined as 1/100 meters.

History/origin: A centimeter is based on the SI unit meter, and as the prefix “centi” indicates, is equal to one hundredth of a meter. Metric prefixes range from factors of 10^-18 to 10¹⁸ based on a decimal system, with the base (in this case the meter) having no prefix and having a factor of 1. Learning some of the more commonly used metric prefixes, such as kilo-, mega-, giga-, tera-, centi-, milli-, micro-, and nano-, can be helpful for quickly navigating metric units.

Current use: The centimeter, like the meter, is used in all sorts of applications worldwide (in countries that have undergone metrication) in instances where a smaller denomination of the meter is required. Height is commonly measured in centimeters outside of countries like the United States.

Inch to Centimeter Conversion Table

Conclusion

The metric system is used in most of the world, but in the United States we still use the imperial system. Americans know the metric system, but many don’t know how to convert inches into centimeters and vise versa.