Millimeters to Inches (mm to in) Converter
1 millimeter (mm) = 0.0393701 inches (in). To convert millimeters to inches, multiply by 0.0393701: 297 mm × 0.0393701 = 11.6929 in. Also searched as millimetres to inches.
Quick facts
- 1 mm = 0.0393701 in
- 1 in = 25.4 mm
- Formula: in = mm × 0.0393701
- Quick estimate: multiply by about 0.039
How to convert millimeters to inches
- Take the value in millimeters.
- Multiply it by 0.0393701 (the number of inches in one millimeter).
- Round the result to the precision you need.
Worked example (the long side of an A4 sheet): 297 mm × 0.0393701 = 11.6929 in, which is about 11 3/4 in.
To convert inches back to millimeters, multiply by 25.4, or divide by 0.0393701.
Source: NIST Special Publication 811 (2008), Appendix B; the international yard and pound agreement of 1959 (1 inch = 25.4 mm exactly).
Millimeters to Inches conversion table
| Millimeters [mm] | Inches [in] | Feet and inches |
|---|---|---|
| 0.01 mm | 0.0003937008 in | under 1/8 in |
| 0.1 mm | 0.0039370079 in | under 1/8 in |
| 1 mm | 0.0393700787 in | under 1/8 in |
| 2 mm | 0.0787401575 in | 1/8 in |
| 3 mm | 0.1181102362 in | 1/8 in |
| 5 mm | 0.1968503937 in | 1/4 in |
| 10 mm | 0.3937007874 in | 3/8 in |
| 20 mm | 0.7874015748 in | 3/4 in |
| 50 mm | 1.968503937 in | 2 in |
| 100 mm | 3.937007874 in | 3 7/8 in |
| 1000 mm | 39.3700787402 in | 3 ft 3 3/8 in |
mm to in chart from 1 to 100
- 1 mm 0.0393701 in
- 2 mm 0.0787402 in
- 3 mm 0.11811 in
- 4 mm 0.15748 in
- 5 mm 0.19685 in
- 6 mm 0.23622 in
- 7 mm 0.275591 in
- 8 mm 0.314961 in
- 9 mm 0.354331 in
- 10 mm 0.393701 in
- 11 mm 0.433071 in
- 12 mm 0.472441 in
- 13 mm 0.511811 in
- 14 mm 0.551181 in
- 15 mm 0.590551 in
- 16 mm 0.629921 in
- 17 mm 0.669291 in
- 18 mm 0.708661 in
- 19 mm 0.748031 in
- 20 mm 0.787402 in
- 25 mm 0.984252 in
- 30 mm 1.1811 in
- 35 mm 1.37795 in
- 40 mm 1.5748 in
- 45 mm 1.77165 in
- 50 mm 1.9685 in
- 55 mm 2.16535 in
- 60 mm 2.3622 in
- 65 mm 2.55906 in
- 70 mm 2.75591 in
- 75 mm 2.95276 in
- 80 mm 3.14961 in
- 85 mm 3.34646 in
- 90 mm 3.54331 in
- 95 mm 3.74016 in
- 100 mm 3.93701 in
Inches to Millimeters conversion table
| Inches [in] | Millimeters [mm] |
|---|---|
| 0.01 in | 0.254 mm |
| 0.1 in | 2.54 mm |
| 1 in | 25.4 mm |
| 2 in | 50.8 mm |
| 3 in | 76.2 mm |
| 5 in | 127 mm |
| 10 in | 254 mm |
| 20 in | 508 mm |
| 50 in | 1270 mm |
| 100 in | 2540 mm |
| 1000 in | 25400 mm |
Millimeters vs Inches
| Millimeter | Inch | |
|---|---|---|
| Symbol | mm | in |
| Equals | 1 mm = 0.0393701 in | 1 in = 25.4 mm |
What is a millimeter?
One thousandth of a meter, the SI base unit of length. Used for small, precise measurements in engineering, printing, and manufacturing tolerances.
What is an inch?
A US customary and imperial unit equal to exactly 25.4 millimeters, with 12 inches to a foot. Used in the US for screen sizes, paper, tools, and rainfall, and in the UK for height.
Frequently asked questions
How many inches are in a millimeter?
There are 0.0393701 inches in 1 millimeter (1 mm = 0.0393700787 in).
How many millimeters are in an inch?
There are 25.4 millimeters in 1 inch (1 in = 25.4 mm).
How do I convert millimeters to inches?
Multiply the number of millimeters by 0.0393701. For example, 10 mm × 0.0393701 = 0.393701 in. To convert back, multiply by 25.4.
What is 10 mm in inches?
10 mm = 0.393701 in (3/8 in).
What is 100 mm in inches?
100 mm = 3.93701 in (3 7/8 in).
Is the conversion exact?
Yes. The factor comes from the official definitions of both units (NIST Special Publication 811 (2008), Appendix B; the international yard and pound agreement of 1959 (1 inch = 25.4 mm exactly)). Results are shown to up to 10 decimal places; round them to suit your purpose.
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