Convert Inches to Centimeters Instantly
Use this Inches to Centimeters converter to change any length from inches (in) into centimeters (cm) with an exact conversion factor. Enter whole or decimal inches to see centimeters, millimeters, feet, yards and meters, or switch to the reverse converter when your starting measurement is already in centimeters.
Convert inches to centimeters, reverse centimeters to inches, combine inches with extra centimeters, or convert one length across common U.S. customary and metric units.
Enter inches to calculate the equivalent length in centimeters and other common units.
Decimals are supported, such as 0.25, 5.5 or 12.75 inches.
Reverse the conversion by dividing centimeters by 2.54.
Useful when a measurement contains inches plus an additional metric length in centimeters.
Enter one length value and choose its unit to convert it into inches, centimeters, millimeters, feet, yards and meters.
Converting inches to centimeters is straightforward because the relationship between the two units is fixed. The international inch is defined as exactly 25.4 millimeters, which is exactly 2.54 centimeters. Therefore, any inch measurement can be converted to centimeters by multiplying it by 2.54.
This inches to centimeters conversion is useful because inches are common in U.S. customary measurements while centimeters are widely used in metric specifications, product dimensions, science, engineering, healthcare, education, manufacturing and international commerce. When a size is supplied in inches but a drawing, form or product specification expects centimeters, applying the exact factor keeps the measurement consistent.
Example: 12 inches × 2.54 = 30.48 centimeters.
Example: 25.4 cm ÷ 2.54 = 10 inches.
Centimeters and inches both measure length, not area or volume. One centimeter is one hundredth of a meter, while an inch belongs to the U.S. customary and imperial family of length units. The two systems can be compared reliably because the inch has an exact metric definition.
The chart below provides common inch measurements in centimeters, millimeters and meters. It is useful for quick reference when comparing screen sizes, furniture dimensions, clothing measurements, tools, craft materials, drawings and product specifications.
| Inches | Centimeters | Millimeters | Meters |
|---|---|---|---|
| 0.25 in | 0.635 cm | 6.35 mm | 0.00635 m |
| 0.5 in | 1.27 cm | 12.7 mm | 0.0127 m |
| 1 in | 2.54 cm | 25.4 mm | 0.0254 m |
| 2 in | 5.08 cm | 50.8 mm | 0.0508 m |
| 3 in | 7.62 cm | 76.2 mm | 0.0762 m |
| 4 in | 10.16 cm | 101.6 mm | 0.1016 m |
| 5 in | 12.7 cm | 127 mm | 0.127 m |
| 6 in | 15.24 cm | 152.4 mm | 0.1524 m |
| 8 in | 20.32 cm | 203.2 mm | 0.2032 m |
| 10 in | 25.4 cm | 254 mm | 0.254 m |
| 12 in | 30.48 cm | 304.8 mm | 0.3048 m |
| 18 in | 45.72 cm | 457.2 mm | 0.4572 m |
| 24 in | 60.96 cm | 609.6 mm | 0.6096 m |
| 36 in | 91.44 cm | 914.4 mm | 0.9144 m |
| 48 in | 121.92 cm | 1,219.2 mm | 1.2192 m |
| 60 in | 152.4 cm | 1,524 mm | 1.524 m |
| 72 in | 182.88 cm | 1,828.8 mm | 1.8288 m |
| 100 in | 254 cm | 2,540 mm | 2.54 m |
1 × 2.54 = 2.54 cm.
6 × 2.54 = 15.24 cm.
12 × 2.54 = 30.48 cm.
24 × 2.54 = 60.96 cm.
Multiply 7.5 by 2.54. The result is 19.05 centimeters. Decimal inch values do not require a different formula; the same exact factor applies to whole numbers, decimals and fraction-equivalent values.
Three-quarters of an inch equals 0.75 inch. Multiply 0.75 × 2.54 to get 1.905 centimeters. This is useful when a U.S. measurement is written as a common fraction but a metric specification needs decimal centimeters.
32 × 2.54 = 81.28 centimeters. Keeping the full result can matter for fitted parts, product dimensions or technical layouts where premature rounding could create a noticeable mismatch.
The modern international inch is tied directly to the metric system. It is exactly 25.4 millimeters. Since one centimeter contains 10 millimeters, 25.4 millimeters equals 2.54 centimeters. This exact definition provides a consistent bridge between customary inch measurements and metric length measurements.
For practical conversions, this means you do not need different factors for construction, clothing, screens, machine parts or everyday objects. The factor itself stays the same. What can differ is the precision of the original measurement and the number of decimal places appropriate for the task.
For authoritative background on U.S. customary and SI length relationships, see the NIST guidance on SI units of length. For the international SI framework, the BIPM SI Brochure is a primary reference.
The same physical length can be labeled 1 inch in customary units or exactly 2.54 centimeters in metric units.
An inches to centimeters converter is useful whenever dimensions cross between customary and metric systems. Consumer products sold internationally may list dimensions in both inches and centimeters. Clothing and body measurements may be recorded in inches while a size chart uses centimeters. Craft patterns, sewing guides and woodworking plans can also mix the two systems.
Technology is another common example. Display diagonals are often marketed in inches, while desks, cases, mounting spaces and product packaging may be documented in centimeters. Converting the measurement helps you compare specifications without estimating visually.
In education and science, metric units are standard in many contexts, so a measurement collected with an inch-marked ruler may need conversion before it is entered in a worksheet or report. In fabrication and repair, the same issue can appear when a customary drawing meets a metric component specification.
An inch, centimeter and millimeter all measure linear distance, but their sizes and measurement systems differ. An inch is larger than a centimeter: one inch is exactly 2.54 centimeters. A centimeter is larger than a millimeter: one centimeter equals exactly 10 millimeters. Therefore one inch equals exactly 25.4 millimeters.
Measurements are supplied in U.S. customary format, such as many household dimensions, hardware sizes, screen diagonals, lumber dimensions, craft instructions or U.S.-focused product specifications.
You need metric dimensions for international specifications, clothing measurements, schoolwork, medical or body measurements, product packaging, design documents or general SI-compatible communication.
Fractional inches are common in tape-measure readings and hardware dimensions. Convert the fraction to a decimal and then multiply by 2.54. For example, 1/2 inch is 0.5 inch, so it equals 1.27 centimeters. A quarter inch is 0.25 inch, which equals 0.635 centimeters. Three-quarters of an inch is 0.75 inch, which equals 1.905 centimeters.
For mixed measurements such as 2 3/8 inches, first convert 3/8 to 0.375 and add it to 2, giving 2.375 inches. Then multiply 2.375 × 2.54 = 6.0325 centimeters. If your application needs millimeters, multiply centimeters by 10, giving 60.325 mm.
| Fractional Inch | Decimal Inch | Centimeters | Millimeters |
|---|---|---|---|
| 1/8 in | 0.125 in | 0.3175 cm | 3.175 mm |
| 1/4 in | 0.25 in | 0.635 cm | 6.35 mm |
| 3/8 in | 0.375 in | 0.9525 cm | 9.525 mm |
| 1/2 in | 0.5 in | 1.27 cm | 12.7 mm |
| 5/8 in | 0.625 in | 1.5875 cm | 15.875 mm |
| 3/4 in | 0.75 in | 1.905 cm | 19.05 mm |
| 7/8 in | 0.875 in | 2.2225 cm | 22.225 mm |
To reverse the conversion, divide centimeters by 2.54. For example, 50 centimeters ÷ 2.54 equals approximately 19.685 inches. The result can be kept as a decimal inch value or rounded according to the precision you actually need.
When a familiar exact counterpart exists, the calculation is especially simple. 2.54 cm equals exactly 1 inch, 30.48 cm equals exactly 12 inches or 1 foot, and 91.44 cm equals exactly 36 inches or 1 yard. The reverse calculator above performs the division automatically and also reports related units.
The conversion factor is exact, but your original measurement may not be. A product listed as 8 inches wide may have been rounded to the nearest inch; reporting 20.320000 cm would imply more precision than the source measurement supports. For general comparisons, one or two decimal places is often readable. For machining, engineering or fitted components, retain the precision required by the drawing, tolerance or specification.
A useful rule is to preserve more digits during the calculation and round only the final displayed result. This reduces cumulative errors when several converted dimensions are added or compared. The calculator keeps enough precision for practical use while formatting very long decimal results for readability.
2.54 is the exact conversion factor. Using 2.5 introduces avoidable error.
Multiply inches by 2.54. Divide centimeters by 2.54 when converting back.
One inch is 2.54 cm but 25.4 mm. The decimal position matters.
Keep extra digits during intermediate steps and round at the end.
Inches and centimeters here are linear units. Square-inch conversions require a squared factor.
A linear conversion must not be reused directly for area. One inch of length equals 2.54 centimeters, but one square inch is a square measuring one inch on each side. Because both dimensions are converted, the factor is squared: 2.54 × 2.54 = 6.4516. Therefore, one square inch equals exactly 6.4516 square centimeters.
The same idea applies to cubic measurements, where the factor would be cubed. Use this page for ordinary length measurements only. If your source measurement includes in² or in³, you need an area or volume converter rather than this linear inches-to-centimeters tool.
Continue converting common length measurements with our related tools: Centimeters to Inches, Inches to Millimeters, Inches to Feet, Yards to Inches, Centimeters to Feet and Meters to Centimeters. Using dedicated conversion pages can make it easier to verify formulas, compare common values and move between metric and customary measurements without mixing factors.
For technical work, it is helpful to distinguish the exact conversion relationship from the precision of a real-world measurement. This page uses the international inch relationship of exactly 25.4 millimeters, equivalent to exactly 2.54 centimeters.
Quick answers about inch, centimeter and metric length conversions.