CM to Inches Converter
This converter is able to convert between centimeters and inches.
First, choose your input unit as cm (centimeters), inches, or feet with inches.
In case your input unit is CM, input the value as a whole or a decimal number. If you chose inches, you have the option to also input fractional inches, if necessary. With feet and inches, you input feet separately and then input inches, including the fractional part.
Once you are happy with your choice and data input, choose the number of decimal places you want your result to be rounded to and click on CONVERT.
You will receive your result in cm and mm, rounded to the selected number of decimal places, in case you chose imperial units (which are feet and inches).
In case you chose a metric unit (centimeters in the case of this calculator), then you will receive a result in inches or feet and inches (in decimal and fractional forms).
The calculator also has a chart icon, which opens a list of conversions between the units banded into ranges in increasing order.
Converting CM to Inches Manually
The conversion is derived from the relationship between inches and centimeters, which is that 1 inch is equal to approximately 2.54 cm (when rounded to 2 decimal places). From this relationship, we can easily derive the following formula:
inches = cm \div 2.54
or
cm = inches * 2.54
Additionally, we must also remember that the number of feet is converted to inches based on the relationship of 1 foot containing 12 inches.
Hence we create these formulae:
feet = inches \div 12
or
inches = feet * 12
Let’s look at two examples of conversion problems below.
EXAMPLE 1: Chris is 177 cm tall. Convert his height to feet and inches.
First, we will convert Chris’ height to inches only, using the formula above.
inches = 177 \div 2.54 = \\69.69 ~inches.
Now we divide 69.69 by 12. However, we will not perform this division towards a decimal number, instead, we will perform it with a decimal remainder.
69.69 ~feet \div 12 = 5 \\~whole ~feet ~and ~a ~remainder.
To find the remainder, we first calculate how many inches the 5 whole feet have as 5×12 = 60.
We subtract 60 from the original number of inches and get 69.69 – 60 = 9.69.
Hence, Chris is 5 feet and 9.69 inches tall.
EXAMPLE 2: Carl is using a 5-inch ruler. How many cm long is the ruler?
We use the formula for calculating cm from inches and plug in 5 as follows:
cm = 5 * 2.54
cm = 12.7
Carl’s ruler is 12.7 cm long.
Metric and Imperial Units
Imperial units originate in England and represent a standardized form of units that have been commonly used in England and some parts of Europe for centuries. The issue with these units was that they referred to body parts, which would differ from person to person. This created difficulties with trade, as people were getting different deals, based on the seller, which lead to overpaying or losses. Imperial units are currently only used in 3 nations as the primary units: the USA, Liberia, and Myanmar.
On the contrary, the metric system originates in France and it was created as a response to the issues that inconsistent units created for trade. These units are based on references that are universal and can be observed in physics and nature, making them more consistent and hence practical. Another advantage is, that all conversions in the metric system follow the base 10 rule, making conversions much easier.
For more information on the differences and history of these two systems, read the article under the CM TO FEET CONVERTER.
Conversion Comparisons
The need to convert between metric and imperial units can be an important one when traveling or shopping online. For example, if a French person wants to order a bed frame from the USA, they will probably receive the dimensions in inches. Computer screen diameters are also almost exclusively given in inches. Engineers use the metric system, hence if an engineer from the USA works on a European project, a good approximation of conversions is a must.
Here is a table with a couple of common items and their sizes in both metric and imperial units.
ITEM | METRIC | IMPERIAL |
---|---|---|
Average smartphone size (diagonal length) | 15.24 cm | 6 inches |
Average adult height (worldwide average) | 165 cm | 5 feet and 5 inches |
Average banana bought in a store in the USA | 18 cm | 7.1 inches |
Average lamppost height in the USA | 366 cm | 12 feet |