Inches to Millimeters Conversion | How many mm in an inch?

There are 25.4 mm in an inch (1 in = 25.4 mm).

To find out how many millimeters (mm) in "x" inches or inches in "x" millimeters, enter an inch or a millimeter value into the converter and the result will be displayed.

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Inches to millimeters length units conversion factor is 25.4. To find out how many millimeters in inches multiply the inch value by 25.4.

1 Inch = 25.4 Millimeters

There are 25.4 millimeters in an inch, because for both imperial and US Customary measurement systems, one foot is defined as 30.48 centimeters (or 304.8 millimeters) exactly by an international agreements and there are 12 inches in a foot, that makes 304.8 / 12 = 25.4 mm in an inch.

For example, to find out how many millimeters there are in an inch and a half, multiply the inch value by the conversion factor, that makes 1.5 * 25.4 = 38.1 millimeters in 1.5 inches.

Inch is an imperial and US Customary measurement systems length unit. 1 inch equals to 25.4 millimeters and 2.54 centimeters. The abbreviation is "in".

Millimeter is a metric length unit and equal to one thousandth of a meter. It is used to measure small distances in engineering and machining. The abbreviation is "mm".

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To create your own custom conversion table click "Create Table" botton. To change values, you may enter a "Start" value (1, 2.5, 5 etc), select a an "Increment" value (0.01, 5, 100 etc) and select an "Accuracy" value to round the result.

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Inches to Millimeters Conversion Table

Inch	Millimeter	Inch	Millimeter	Inch	Millimeter	Inch	Millimeter
1	25.4	26	660.4	51	1295.4	76	1930.4
2	50.8	27	685.8	52	1320.8	77	1955.8
3	76.2	28	711.2	53	1346.2	78	1981.2
4	101.6	29	736.6	54	1371.6	79	2006.6
5	127	30	762	55	1397	80	2032
6	152.4	31	787.4	56	1422.4	81	2057.4
7	177.8	32	812.8	57	1447.8	82	2082.8
8	203.2	33	838.2	58	1473.2	83	2108.2
9	228.6	34	863.6	59	1498.6	84	2133.6
10	254	35	889	60	1524	85	2159
11	279.4	36	914.4	61	1549.4	86	2184.4
12	304.8	37	939.8	62	1574.8	87	2209.8
13	330.2	38	965.2	63	1600.2	88	2235.2
14	355.6	39	990.6	64	1625.6	89	2260.6
15	381	40	1016	65	1651	90	2286
16	406.4	41	1041.4	66	1676.4	100	254
17	431.8	42	1066.8	67	1701.8	125	3175
18	457.2	43	1092.2	68	1727.2	150	381
19	482.6	44	1117.6	69	1752.6	175	4445
20	508	45	1143	70	1778	200	508
21	533.4	46	1168.4	71	1803.4	250	635
22	558.8	47	1193.8	72	1828.8	300	762
23	584.2	48	1219.2	73	1854.2	500	1270
24	609.6	49	1244.6	74	1879.6	750	1905
25	635	50	127	75	1905	1000	2540

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