Length

Mils to Micrometers Converter

Convert mils (mil) to micrometers (µm). 1 mil = 25.4 micrometers (exact)

1 mil (thou) = 25.4 micrometers

How to convert mils to micrometers

Formulaµm = mil × 25.4

Multiply the value in mils by 25.4. To go the other way, multiply by 0.03937007874 (or divide by 25.4).

A mil is larger than a micrometer: one mil contains 25.4 micrometers.

Worked examples

  • 1 mil (thou)1 mil × 25.4 = 25.4 µm
  • 5 mils5 mil × 25.4 = 127 µm
  • 10 mils10 mil × 25.4 = 254 µm
  • 20 mils20 mil × 25.4 = 508 µm
  • 100 mils100 mil × 25.4 = 2,540 µm

Mils to micrometers conversion table

Values are calculated by the conversion engine and rounded to 8 significant figures.

Mils to micrometers: 0.1–10 mil
Mils (mil)Micrometers (µm)
0.1 mil2.54 µm
0.25 mil6.35 µm
0.5 mil12.7 µm
1 mil25.4 µm
2 mil50.8 µm
3 mil76.2 µm
4 mil101.6 µm
5 mil127 µm
6 mil152.4 µm
7 mil177.8 µm
8 mil203.2 µm
9 mil228.6 µm
10 mil254 µm
Mils to micrometers: 12–1,000 mil
Mils (mil)Micrometers (µm)
12 mil304.8 µm
15 mil381 µm
20 mil508 µm
25 mil635 µm
30 mil762 µm
40 mil1,016 µm
50 mil1,270 µm
75 mil1,905 µm
100 mil2,540 µm
250 mil6,350 µm
500 mil12,700 µm
1,000 mil25,400 µm

About the units

Mil (mil)

One thousandth of an inch (0.0254 mm). Used for plastic-film and coating thickness and machining tolerances. One mil equals 0.0000254 meters (m).

Micrometer (µm)

One millionth of a metre, often called a micron. Human hair is roughly 50–100 µm across, and filter and particle sizes are given in micrometres. One micrometer equals 0.000001 meters (m).

Frequently asked questions

How many micrometers are in one mil?

There are 25.4 micrometers in one mil, and this value is exact by definition.

How do I convert mils to micrometers?

Multiply the number of mils by 25.4. For example, 10 mil × 25.4 = 254 µm.

How many mils are in one micrometer?

One micrometer equals 0.03937007874 mils. That is the reverse factor, 1 ÷ 25.4.

What is 10 mils in micrometers?

10 mil = 254 µm.

Is this mil to µm converter accurate?

Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.

Convert mils to other units

Convert other units to micrometers

Try “psi to bar”, “cups”, “binary” or “5 ft in cm”.