A centimeter (cm) is one hundredth of a meter. To convert cm to inches, divide by 2.54, because 1 inch is defined as exactly 2.54 cm.
1 inch = 2.54 cm
Exactly, by definition · 1 cm ≈ 0.3937 in · inches = centimeters ÷ 2.54
- Inches
- ≈ 3.937 in
- Nearest 1/16″
- 3 15/16″ 10 cm is 0.01 mm shorter
- Nearest 1/32″
- 3 15/16″ 10 cm is 0.01 mm shorter
- Nearest 1/64″
- 3 15/16″ 10 cm is 0.01 mm shorter
What is a cm to inches converter?
A cm to inches converter turns a length in centimeters into inches. This one shows the decimal value and the nearest 1/16, 1/32 and 1/64 inch fraction, and says whether your length is slightly more or slightly less than that fraction. That matters when you are reading a tape measure or ruler.
How to convert cm to inches
- Take the length in centimeters.
- Divide it by 2.54.
- The result is the length in inches. Round it to the precision you need.
- For a tape measure, find the nearest fraction (1/16, 1/32 or 1/64) and check whether your length is a little more or less than it.
Formula: inches = centimeters ÷ 2.54
Worked example: 15 cm ÷ 2.54 = 5.9055… in, which rounds to ≈ 5.906 in. The nearest 1/16 inch is 5 7/8″ (5.875 in), and 15 cm is about 0.78 mm longer than that.
To go the other way, multiply inches by 2.54. For example, 10 inches × 2.54 = 25.4 cm exactly.
No calculator? Dividing by 2.5 gives a quick estimate that is about 1.6% too high.
CM to inches chart (1 to 100 cm)
Every centimeter from 1 to 100 with its decimal inches and nearest 1/16 and 1/32 inch fraction. Print it for your workshop or desk.
Decimals are rounded to 3 places. In the fraction columns, + means the value is slightly longer than the fraction, − slightly shorter, and = exact.
| Centimeters (cm) | Inches (decimal) | Nearest 1/16″ | Nearest 1/32″ |
|---|---|---|---|
| 1 cm | 0.394 | 3/8″ + | 13/32″ − |
| 2 cm | 0.787 | 13/16″ − | 25/32″ + |
| 3 cm | 1.181 | 1 3/16″ − | 1 3/16″ − |
| 4 cm | 1.575 | 1 9/16″ + | 1 9/16″ + |
| 5 cm | 1.969 | 1 15/16″ + | 1 31/32″ − |
| 6 cm | 2.362 | 2 3/8″ − | 2 3/8″ − |
| 7 cm | 2.756 | 2 3/4″ + | 2 3/4″ + |
| 8 cm | 3.15 | 3 1/8″ + | 3 5/32″ − |
| 9 cm | 3.543 | 3 9/16″ − | 3 17/32″ + |
| 10 cm | 3.937 | 3 15/16″ − | 3 15/16″ − |
| 11 cm | 4.331 | 4 5/16″ + | 4 11/32″ − |
| 12 cm | 4.724 | 4 3/4″ − | 4 23/32″ + |
| 13 cm | 5.118 | 5 1/8″ − | 5 1/8″ − |
| 14 cm | 5.512 | 5 1/2″ + | 5 1/2″ + |
| 15 cm | 5.906 | 5 7/8″ + | 5 29/32″ − |
| 16 cm | 6.299 | 6 5/16″ − | 6 5/16″ − |
| 17 cm | 6.693 | 6 11/16″ + | 6 11/16″ + |
| 18 cm | 7.087 | 7 1/16″ + | 7 3/32″ − |
| 19 cm | 7.48 | 7 1/2″ − | 7 15/32″ + |
| 20 cm | 7.874 | 7 7/8″ − | 7 7/8″ − |
| 21 cm | 8.268 | 8 1/4″ + | 8 9/32″ − |
| 22 cm | 8.661 | 8 11/16″ − | 8 21/32″ + |
| 23 cm | 9.055 | 9 1/16″ − | 9 1/16″ − |
| 24 cm | 9.449 | 9 7/16″ + | 9 7/16″ + |
| 25 cm | 9.843 | 9 13/16″ + | 9 27/32″ − |
| 26 cm | 10.236 | 10 1/4″ − | 10 1/4″ − |
| 27 cm | 10.63 | 10 5/8″ + | 10 5/8″ + |
| 28 cm | 11.024 | 11″ + | 11 1/32″ − |
| 29 cm | 11.417 | 11 7/16″ − | 11 13/32″ + |
| 30 cm | 11.811 | 11 13/16″ − | 11 13/16″ − |
| 31 cm | 12.205 | 12 3/16″ + | 12 7/32″ − |
| 32 cm | 12.598 | 12 5/8″ − | 12 19/32″ + |
| 33 cm | 12.992 | 13″ − | 13″ − |
| 34 cm | 13.386 | 13 3/8″ + | 13 3/8″ + |
| 35 cm | 13.78 | 13 3/4″ + | 13 25/32″ − |
| 36 cm | 14.173 | 14 3/16″ − | 14 3/16″ − |
| 37 cm | 14.567 | 14 9/16″ + | 14 9/16″ + |
| 38 cm | 14.961 | 14 15/16″ + | 14 31/32″ − |
| 39 cm | 15.354 | 15 3/8″ − | 15 11/32″ + |
| 40 cm | 15.748 | 15 3/4″ − | 15 3/4″ − |
| 41 cm | 16.142 | 16 1/8″ + | 16 5/32″ − |
| 42 cm | 16.535 | 16 9/16″ − | 16 17/32″ + |
| 43 cm | 16.929 | 16 15/16″ − | 16 15/16″ − |
| 44 cm | 17.323 | 17 5/16″ + | 17 5/16″ + |
| 45 cm | 17.717 | 17 11/16″ + | 17 23/32″ − |
| 46 cm | 18.11 | 18 1/8″ − | 18 1/8″ − |
| 47 cm | 18.504 | 18 1/2″ + | 18 1/2″ + |
| 48 cm | 18.898 | 18 7/8″ + | 18 29/32″ − |
| 49 cm | 19.291 | 19 5/16″ − | 19 9/32″ + |
| 50 cm | 19.685 | 19 11/16″ − | 19 11/16″ − |
| 51 cm | 20.079 | 20 1/16″ + | 20 3/32″ − |
| 52 cm | 20.472 | 20 1/2″ − | 20 15/32″ + |
| 53 cm | 20.866 | 20 7/8″ − | 20 7/8″ − |
| 54 cm | 21.26 | 21 1/4″ + | 21 1/4″ + |
| 55 cm | 21.654 | 21 5/8″ + | 21 21/32″ − |
| 56 cm | 22.047 | 22 1/16″ − | 22 1/16″ − |
| 57 cm | 22.441 | 22 7/16″ + | 22 7/16″ + |
| 58 cm | 22.835 | 22 13/16″ + | 22 27/32″ − |
| 59 cm | 23.228 | 23 1/4″ − | 23 7/32″ + |
| 60 cm | 23.622 | 23 5/8″ − | 23 5/8″ − |
| 61 cm | 24.016 | 24″ + | 24 1/32″ − |
| 62 cm | 24.409 | 24 7/16″ − | 24 13/32″ + |
| 63 cm | 24.803 | 24 13/16″ − | 24 13/16″ − |
| 64 cm | 25.197 | 25 3/16″ + | 25 3/16″ + |
| 65 cm | 25.591 | 25 9/16″ + | 25 19/32″ − |
| 66 cm | 25.984 | 26″ − | 25 31/32″ + |
| 67 cm | 26.378 | 26 3/8″ + | 26 3/8″ + |
| 68 cm | 26.772 | 26 3/4″ + | 26 25/32″ − |
| 69 cm | 27.165 | 27 3/16″ − | 27 5/32″ + |
| 70 cm | 27.559 | 27 9/16″ − | 27 9/16″ − |
| 71 cm | 27.953 | 27 15/16″ + | 27 15/16″ + |
| 72 cm | 28.346 | 28 3/8″ − | 28 11/32″ + |
| 73 cm | 28.74 | 28 3/4″ − | 28 3/4″ − |
| 74 cm | 29.134 | 29 1/8″ + | 29 1/8″ + |
| 75 cm | 29.528 | 29 1/2″ + | 29 17/32″ − |
| 76 cm | 29.921 | 29 15/16″ − | 29 29/32″ + |
| 77 cm | 30.315 | 30 5/16″ + | 30 5/16″ + |
| 78 cm | 30.709 | 30 11/16″ + | 30 23/32″ − |
| 79 cm | 31.102 | 31 1/8″ − | 31 3/32″ + |
| 80 cm | 31.496 | 31 1/2″ − | 31 1/2″ − |
| 81 cm | 31.89 | 31 7/8″ + | 31 7/8″ + |
| 82 cm | 32.283 | 32 5/16″ − | 32 9/32″ + |
| 83 cm | 32.677 | 32 11/16″ − | 32 11/16″ − |
| 84 cm | 33.071 | 33 1/16″ + | 33 1/16″ + |
| 85 cm | 33.465 | 33 7/16″ + | 33 15/32″ − |
| 86 cm | 33.858 | 33 7/8″ − | 33 27/32″ + |
| 87 cm | 34.252 | 34 1/4″ + | 34 1/4″ + |
| 88 cm | 34.646 | 34 5/8″ + | 34 21/32″ − |
| 89 cm | 35.039 | 35 1/16″ − | 35 1/32″ + |
| 90 cm | 35.433 | 35 7/16″ − | 35 7/16″ − |
| 91 cm | 35.827 | 35 13/16″ + | 35 13/16″ + |
| 92 cm | 36.22 | 36 1/4″ − | 36 7/32″ + |
| 93 cm | 36.614 | 36 5/8″ − | 36 5/8″ − |
| 94 cm | 37.008 | 37″ + | 37″ + |
| 95 cm | 37.402 | 37 3/8″ + | 37 13/32″ − |
| 96 cm | 37.795 | 37 13/16″ − | 37 25/32″ + |
| 97 cm | 38.189 | 38 3/16″ + | 38 3/16″ + |
| 98 cm | 38.583 | 38 9/16″ + | 38 19/32″ − |
| 99 cm | 38.976 | 39″ − | 38 31/32″ + |
| 100 cm | 39.37 | 39 3/8″ − | 39 3/8″ − |
Common sizes in centimeters and inches
The nearest fraction is the closest 1/16 inch. The last column shows how far off it is, so you can see when an inch ruler will not be a true match for a metric size.
Cards and paper sizes
| Item | Centimeters | Inches (decimal) | Nearest fraction | Difference |
|---|---|---|---|---|
| Business card (width) | 9 cm | 3.543 | ≈ 3 9/16″ | 0.49 mm shorter |
| Credit card (width) | 8.56 cm | 3.37 | ≈ 3 3/8″ | 0.12 mm shorter |
| A6 paper (long side) | 14.8 cm | 5.827 | ≈ 5 13/16″ | 0.36 mm longer |
| A4 paper (width) | 21 cm | 8.268 | ≈ 8 1/4″ | 0.45 mm longer |
| A4 paper (length) | 29.7 cm | 11.693 | ≈ 11 11/16″ | 0.14 mm longer |
| A3 paper (length) | 42 cm | 16.535 | ≈ 16 9/16″ | 0.69 mm shorter |
A4 paper is close to US Letter (8.5 × 11 in) but not the same: it is narrower and longer.
Frequently asked questions
How many inches is 1 cm?
1 cm is exactly 1/2.54 inch, which is about 0.3937 inch. Because the result does not end, it is written with the approximately-equal sign.
How many cm are in an inch?
There are exactly 2.54 cm in 1 inch. This is a definition, not a rounded value.
What is 10 cm in inches?
10 cm is about 3.937 inch. The nearest 1/16 inch is 3 15/16 inch, and 10 cm is slightly shorter than that, by about 0.01 mm.
What is 15 cm in inches?
15 cm is about 5.906 inch. The nearest 1/16 inch is 5 7/8 inch, and 15 cm is slightly longer than that, by about 0.78 mm.
What is 30 cm in inches?
30 cm is about 11.811 inch. The nearest 1/16 inch is 11 13/16 inch, and 30 cm is slightly shorter than that, by about 0.04 mm.
How do I convert cm to inches without a calculator?
Divide the centimeters by 2.5 for a quick estimate. It is about 1.6% too high, because the exact divisor is 2.54. For exact work, divide by 2.54.
Is 1 inch exactly 2.54 cm?
Yes. The inch has been defined as exactly 25.4 mm, which is 2.54 cm, since the international yard and pound agreement of 1959, and NIST lists the factor as exact.
What does the ≈ sign mean in these results?
It means the value is rounded. An equals sign is used only when the result is exact, such as 25.4 cm = 10 inches.