inches to mm converter

1 in = 25.4 mm (exact); 1 mm = 0.0393701 in. To convert inches to mm, multiply by 25.4.

Formula: mm = in × 25.4

Conversion table

Common in to mm conversions:

1 in	25.4 mm
2 in	50.8 mm
3 in	76.2 mm
4 in	101.6 mm
5 in	127 mm
6 in	152.4 mm
7 in	177.8 mm
8 in	203.2 mm
9 in	228.6 mm
10 in	254 mm
15 in	381 mm
20 in	508 mm
25 in	635 mm
50 in	1270 mm
100 in	2540 mm
1000 in	25400 mm

Reverse: mm to in

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
15 mm	0.590551 in
20 mm	0.787402 in
25 mm	0.984252 in
50 mm	1.9685 in
100 mm	3.93701 in
1000 mm	39.3701 in

Key facts

1 inch	25.4 mm (exact)
1 millimetre	0.0393701 in
Formula	mm = in × 25.4
0.5 in	12.7 mm

Frequently asked questions

How many mm is 1 inch?

1 inch equals exactly 25.4 mm. Multiply the inch value by 25.4.

How do I convert inches to mm?

Multiply the inch value by 25.4. For example, 2 in × 25.4 = 50.8 mm.

inches to mm is part of OmniConvert on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.

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