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Inches to Millimeters Conversion Information
Converting inches (in) to millimeters (mm) is a common length conversion when transitioning from imperial to metric measurements. This conversion is frequently used in engineering, manufacturing, and international projects where metric measurements are standard.
How to Convert Inches to Millimeters
To convert inches to millimeters, use the following formula:
mm = in × 25.4
Inches to Millimeters Conversion Table
| Inches (in) | Millimeters (mm) | Common Reference |
|---|---|---|
| 0.039 in | 1 mm | Thickness of a credit card |
| 0.25 in | 6.35 mm | Width of a pencil |
| 0.5 in | 12.7 mm | Diameter of a dime |
| 1 in | 25.4 mm | Width of a standard ruler marking |
| 2 in | 50.8 mm | Width of a golf ball |
| 3 in | 76.2 mm | Width of a baseball |
| 6 in | 152.4 mm | Length of a dollar bill |
| 12 in (1 ft) | 304.8 mm | Length of a standard ruler |
Common Inch to Millimeter Conversions
- 1 in = 25.4 mm (exact conversion)
- 2 in = 50.8 mm
- 6 in = 152.4 mm
- 12 in = 304.8 mm
About Inches
The inch (in) is a unit of length in the imperial and US customary systems. It is defined as exactly 25.4 millimeters. In many contexts, the inch is comprised of smaller divisions, such as 1/2 inch, 1/4 inch, 1/8 inch, and so on. Rulers and measuring tapes often display these fractional divisions.
About Millimeters
The millimeter (mm) is a unit of length in the metric system, equal to one-thousandth of a meter. It is commonly used in science, engineering, and manufacturing worldwide. The metric system's decimal structure makes it easier to work with for calculations and precise measurements.
For precision work, it's important to remember that 1 inch equals exactly 25.4 millimeters. This exact conversion was internationally agreed upon in 1959 to standardize the relationship between metric and imperial units.