Convert Inches (in) to Millimeters (mm)

Ever wondered what 1 in equals in mm? It is exactly 25.4 mm, and any other value scales linearly from there.

25.4

Formula

1 in = 25.4 mm

To convert in to mm, multiply the value by 25.4.

Conversion Table

Inches to Millimeters Conversion Table
Inches (in)Millimeters (mm)
0.01 in0.254 mm
0.1 in2.54 mm
0.5 in12.7 mm
1 in25.4 mm
2 in50.8 mm
3 in76.2 mm
5 in127 mm
10 in254 mm
15 in381 mm
20 in508 mm
25 in635 mm
50 in1270 mm
100 in2540 mm
250 in6350 mm
500 in12700 mm
1000 in25400 mm
2500 in63500 mm
5000 in127000 mm
10000 in254000 mm
50000 in1270000 mm

Common in to mm Examples

Frequently Asked Questions

Inches is a standard Length unit used in specific regions or fields. Its definition has been refined over time to match international measurement standards.

Millimeters is a Length unit with its own historical and regional roots, now defined in relation to internationally agreed reference standards.

1 in equals 25.4 mm. This ratio applies to every conversion between the two units.

The formula is 1 in = 25.4 mm. To convert any value, multiply the value by 25.4.

Take the value in in and multiply the value by 25.4. The result is the same value expressed in mm.

The ratio 25.4 is defined to high precision and is exact for most practical purposes. Rounding only matters when many decimal places are needed.