inches to millimeters
1 inch (in) equals 25.4 millimeters (mm). Type a value into either box below for an instant two-way conversion. For other units, use the full unit converter.
Chinese version: 英寸转毫米
Conversion factor
1 in = 25.4 mm
Reverse: 1 mm = 0.0394 in
in to mm conversion table
| in | mm | Detail |
|---|---|---|
| 1 | 25.4 | 1 in to mm |
| 2 | 50.8 | 2 in to mm |
| 3 | 76.2 | 3 in to mm |
| 4 | 101.6 | 4 in to mm |
| 5 | 127 | 5 in to mm |
| 6 | 152.4 | 6 in to mm |
| 7 | 177.8 | 7 in to mm |
| 8 | 203.2 | 8 in to mm |
| 9 | 228.6 | 9 in to mm |
| 10 | 254 | 10 in to mm |
| 20 | 508 | 20 in to mm |
| 25 | 635 | 25 in to mm |
| 30 | 762 | 30 in to mm |
| 40 | 1,016 | 40 in to mm |
| 50 | 1,270 | 50 in to mm |
| 60 | 1,524 | 60 in to mm |
| 70 | 1,778 | 70 in to mm |
| 80 | 2,032 | 80 in to mm |
| 90 | 2,286 | 90 in to mm |
| 100 | 2,540 | 100 in to mm |
| 150 | 3,810 | 150 in to mm |
| 200 | 5,080 | 200 in to mm |
| 250 | 6,350 | 250 in to mm |
| 300 | 7,620 | 300 in to mm |
| 400 | 10,160 | 400 in to mm |
| 500 | 12,700 | 500 in to mm |
| 600 | 15,240 | 600 in to mm |
| 700 | 17,780 | 700 in to mm |
| 800 | 20,320 | 800 in to mm |
| 900 | 22,860 | 900 in to mm |
| 1,000 | 25,400 | 1,000 in to mm |
| 1,500 | 38,100 | 1,500 in to mm |
| 2,000 | 50,800 | 2,000 in to mm |
| 2,500 | 63,500 | 2,500 in to mm |
| 5,000 | 127,000 | 5,000 in to mm |
How to convert
To convert inches to millimeters, multiply: mm = in × 25.4
To convert millimeters to inches, divide: in = mm ÷ 25.4 (equivalently × 0.0394).
Example: 1 inch × 25.4 = 25.4 millimeters. The factor is derived from the international definition of each unit; results are shown to 4 significant figures.
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Disclaimer: conversion factors are derived from international unit definitions and results are for reference only. For trade settlement, engineering or legal documents, follow the contract or official metrology standards.