Thou to millimeters
Type a value in thou to get it in mm instantly.
2.54mm
Nothing on our list is smaller: an ant is 1.97× longer. Walking, you would cover that in 1.814 milliseconds.
Convert the other way: mm to thou
What it means
How long is that?
Reference lengths are typical values. The inch, foot, yard and mile are defined exactly in meters (1 inch = 2.54 cm).
The math
How to convert thou to mm
To convert thou to millimeters, multiply by 0.0254.
Example: 100 thou × 0.0254 = 2.54 mm.
In the other direction, 1 mm = 39.3701 thou.
Every unit
Your length in every unit
Tables
thou to mm conversion table
| thou | mm |
|---|---|
| 1 thou | 0.0254 mm |
| 2 thou | 0.0508 mm |
| 3 thou | 0.0762 mm |
| 5 thou | 0.127 mm |
| 10 thou | 0.254 mm |
| 15 thou | 0.381 mm |
| 20 thou | 0.508 mm |
| 25 thou | 0.635 mm |
| 30 thou | 0.762 mm |
| 50 thou | 1.27 mm |
| 75 thou | 1.905 mm |
| 100 thou | 2.54 mm |
| 150 thou | 3.81 mm |
| 200 thou | 5.08 mm |
| 500 thou | 12.7 mm |
| 1,000 thou | 25.4 mm |
mm to thou conversion table
| mm | thou |
|---|---|
| 1 mm | 39.3701 thou |
| 2 mm | 78.7402 thou |
| 3 mm | 118.11 thou |
| 5 mm | 196.85 thou |
| 10 mm | 393.701 thou |
| 15 mm | 590.551 thou |
| 20 mm | 787.402 thou |
| 25 mm | 984.252 thou |
| 30 mm | 1,181.1 thou |
| 50 mm | 1,968.5 thou |
| 75 mm | 2,952.76 thou |
| 100 mm | 3,937.01 thou |
| 150 mm | 5,905.51 thou |
| 200 mm | 7,874.02 thou |
| 500 mm | 19,685 thou |
| 1,000 mm | 39,370.1 thou |
Quick answers
Quick answers
- How many mm is 1 thou?
- 1 thou is 0.0254 mm.
- How many mm is 10 thou?
- 10 thou is 0.254 mm.
- How many mm is 100 thou?
- 100 thou is 2.54 mm.
The units
About these units
Thou (thou)
A thousandth of an inch, the machinist’s unit. Also called a mil.
Millimeters (mm)
A millimeter is a thousandth of a meter, roughly the thickness of a credit card. It is the everyday unit of engineering drawings and rainfall.
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