Inch to Millimeter Converter
Conversion Formula
Factor
Formula
About Inch
The inch is a unit of length in the imperial and US customary systems. It is defined as exactly 2.54 centimeters.
Facts About Inches
- 1 inch = 2.54 centimeters
- 1 inch = 25.4 millimeters
- 12 inches = 1 foot
- 36 inches = 1 yard
Common Uses
- Screen sizes (TVs, monitors, phones)
- Tire and wheel sizes
- Construction lumber (2x4, etc.)
- Paper sizes (US Letter = 8.5 x 11 inches)
- Rainfall measurements in the US
History
The inch has been used since ancient times. The word "inch" derives from the Latin word "uncia," meaning "one-twelfth," which was also the name of a Roman unit. The inch was originally defined as the width of a man's thumb at the base of the nail.
In 1959, the international yard and pound agreement defined the inch as exactly 25.4 millimeters (2.54 centimeters), establishing a standard conversion between imperial and metric systems. This definition is now used universally in the United States, United Kingdom, Canada, Australia, New Zealand, and South Africa.
About Millimeter
The millimeter is a unit of length equal to one-thousandth of a meter. It is used for precise measurements.
Facts About Millimeters
- 1 millimeter = 0.001 meters
- 1 millimeter = 0.1 centimeters
- 1 millimeter ≈ 0.03937 inches
- 10 millimeters = 1 centimeter
Common Uses
- Precision engineering
- 3D printing specifications
- Rainfall measurements
- Medical measurements
- Jewelry dimensions
History
The millimeter was introduced as part of the metric system in 1795 during the French Revolution. The prefix "milli-" comes from the Latin word "mille," meaning one thousand. The metric system was designed to provide a decimal-based system of measurement that was easy to use and understand.
Since 1983, the meter has been defined as "the length of the path travelled by light in a vacuum during a time interval of 1/299,792,458 of a second." A millimeter, being 1/1000 of a meter, is the distance light travels in 1/299,792,458,000 of a second.
Conversion Table
Inch(in) | Millimeter(mm) |
|---|---|
1 | 25.4 |
2 | 50.8 |
3 | 76.2 |
4 | 101.6 |
5 | 127 |
6 | 152.4 |
7 | 177.8 |
8 | 203.2 |
9 | 228.6 |
10 | 254 |
Conversion Examples
Convert 1 Inch to Millimeter
- Conversion Factor: 1 in = 25.4 mm
- Conversion Formula: mm = in × 25.4
- Calculation: 1 in × 25.4 = 25.4 mm
Convert 10 Inch to Millimeter
- Conversion Factor: 1 in = 25.4 mm
- Conversion Formula: mm = in × 25.4
- Calculation: 10 in × 25.4 = 254 mm
Convert 100 Inch to Millimeter
- Conversion Factor: 1 in = 25.4 mm
- Conversion Formula: mm = in × 25.4
- Calculation: 100 in × 25.4 = 2,540 mm
Convert 1,000 Inch to Millimeter
- Conversion Factor: 1 in = 25.4 mm
- Conversion Formula: mm = in × 25.4
- Calculation: 1,000 in × 25.4 = 25,400 mm