Inches to CM Calculator
Enter inches, with an optional fraction such as 5 3/8, and get centimeters straight away, plus millimeters, meters and feet. One inch is exactly 2.54 centimeters, so 5 3/8 inches is 13.6525 cm.
Last updated November 4, 2026
Whole or decimal inches, 0 up to 1,000,000.
Result
5 3/8 inches = 13.6525 cm
| Unit | Length |
|---|---|
| Centimeters | 13.6525 |
| Millimeters | 136.525 |
| Meters | 0.1365 |
| Feet | 0.4479 |
| Inches (decimal) | 5.375 |
| Size | Inches | Centimeters |
|---|---|---|
| US Letter paper width | 8.5 | 21.59 |
| US Letter paper height | 11 | 27.94 |
| 13-inch laptop screen (diagonal) | 13 | 33.02 |
| 24-inch monitor (diagonal) | 24 | 60.96 |
| 65-inch TV (diagonal) | 65 | 165.1 |
Shoe sizes are not lengths in inches: they follow brand and country scales, so measure your foot in cm and check the maker chart.
Show the work
Formula: centimeters = inches × 2.54 (exact). Mixed number: inches = whole + numerator ÷ denominator.
- You entered 5 3/8 inches.
- Decimal inches: 5 + 3/8 = 5.375.
- Centimeters: 5.375 × 2.54 = 13.6525 cm.
- Millimeters: 13.6525 × 10 = 136.525 mm. Meters: 13.6525 ÷ 100 = 0.1365 m.
- Feet: 5.375 ÷ 12 = 0.4479 ft.
Result: 5 3/8 inches = 13.6525 cm
How inches convert to centimeters
centimeters = inches × 2.54
millimeters = centimeters × 10
meters = centimeters ÷ 100
feet = inches ÷ 12
The inch is defined through the metric system. Under the international yard and pound agreement of 1959, one inch equals exactly 25.4 millimeters, which is 2.54 centimeters. The factor has no rounding in it, so any difference you see between two converters comes from how they round the answer, not from the constant.
The calculator first turns your entry into decimal inches. A mixed number adds the whole part to the fraction, so 5 3/8 becomes 5 + 3 ÷ 8 = 5.375. It then multiplies by 2.54. Feet come from dividing the inches by 12, and meters from dividing the centimeters by 100.
To go the other way, divide centimeters by 2.54. The two directions are exact inverses, so a value converted there and back returns the number you started with, apart from the rounding shown on screen.
See how we calculate for the formulas, sources and review schedule behind every calculator.
Also useful alongside this calculator: Feet to Meters Converter and Meters to Feet Converter.
Entering fractions of an inch
Tape measures, drill bits and woodworking plans are marked in fractions rather than decimals. Type the whole inches in the first box and pick the fraction from the list, which offers every sixteenth from 1/16 to 15/16 in reduced form. For 5 3/8 inches, enter 5 and choose 3/8.
For a bare fraction such as 1/2 inch, enter 0 and choose 1/2. If you already have a decimal like 2.75, type it in the first box and leave the fraction on None. For finer marks such as 1/32 or 1/64, convert them to a decimal first by dividing the top number by the bottom.
Paper, screens and other common sizes
US Letter paper is 8.5 by 11 inches, which is 21.59 by 27.94 cm. Screen sizes are quoted as the diagonal of the display: a 13-inch laptop is 33.02 cm across the diagonal, a 24-inch monitor is 60.96 cm and a 65-inch TV is 165.1 cm.
A screen diagonal is not its width. The width and height depend on the aspect ratio, so measure the actual panel if you are fitting it into a cabinet. The table under the result lists these sizes so you can compare them at a glance.
A caution about shoe sizes
A shoe size is not a length in inches. US, UK and European scales start from different points and use different steps, and the same number can fit differently between brands. Converting a size number with this calculator would give a meaningless result.
Instead, measure the length of your foot in centimeters, then compare it with the size chart of the maker. If you only have inches, enter them here to get centimeters first.
Rounding and limits
The input must be a finite number from 0 up to 1,000,000 inches. Negative lengths are rejected because a length cannot be below zero. Results are rounded to four decimals for display only, so 1 inch shows as 2.54 and 5 3/8 inches as 13.6525.
The Show the work panel prints each multiplication and division from the values you entered, so you can repeat it on any calculator.
How to use the Inches to CM Calculator
- Type the whole or decimal inches in the Inches box.
- Pick a fraction of an inch from the list, or leave it on None.
- Read the centimeters in the headline, plus millimeters, meters and feet in the list.
- Compare with the common sizes table for paper and screens.
- Open Show the work to see each step, or use Copy, Print or Share.
Worked example
A board measures 5 3/8 inches. As a decimal that is 5 + 3 ÷ 8 = 5.375 inches. Multiplying by 2.54 gives 13.6525 cm, which is 136.525 mm or 0.1365 m, and 0.4479 feet.
| Inches | Centimeters |
|---|---|
| 1/2 | 1.27 |
| 1 | 2.54 |
| 4 | 10.16 |
| 8 1/2 | 21.59 |
| 12 | 30.48 |
| 36 | 91.44 |
Frequently asked questions
How many centimeters are in an inch?
One inch is exactly 2.54 centimeters, or 25.4 millimeters. The value is a definition agreed in 1959, so it is not rounded or approximate.
How do I convert a fraction like 5 3/8 inches to cm?
Add the fraction to the whole number to get decimal inches, 5 + 3/8 = 5.375, then multiply by 2.54. That gives 13.6525 cm for 5 3/8 inches.
How many cm is 12 inches?
Twelve inches is one foot, which is exactly 30.48 centimeters. Multiply any number of inches by 2.54 to check other lengths the same way.
Can I convert a shoe size from inches to centimeters?
Not reliably. Shoe sizes follow country and brand scales rather than a fixed length. Measure your foot in centimeters and use the size chart of the maker.