Convert Micrometers to Mils
1 micrometer (µm) equals 0.03937007874 mils (mil).
1 µm = 0.03937007874 mil
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk micrometer to mil converter to paste a column from Excel.
How to Convert Micrometer to Mil
- 1 µm = 0.03937007874 mil
- 1 mil = 25.4 µm
- Example: convert 15 µm to mil: 15 µm = 15 × 0.03937007874 mil = 0.5905511811 mil
Formula
mil = µm × 0.03937007874016
or mil = µm ÷ 25.4
Derivation from SI units:
- 1 µm = 10⁻⁶ m
- 1 mil = 0.001 in = 25.4 µm (exact)
- 1 µm = 0.000001 m ÷ 0.0000254 m per mil = 0.03937007874016 mil
Both units are defined exactly, so the factor is exact. Micrometer definition: micrometer; Mil definition: mil.
Worked examples
- A reading of 5 µm converts to 0.1968503937 mil.
5 µm × 0.03937007874 = 0.1968503937 mil - A value of 75 µm is 2.952755906 mil.
75 µm × 0.03937007874 = 2.952755906 mil
Micrometer to Mil conversion table
| Micrometers (µm) | Mils (mil) |
|---|---|
| 0.1 µm | 0.003937007874 mil |
| 0.3 µm | 0.01181102362 mil |
| 0.5 µm | 0.01968503937 mil |
| 1 µm | 0.03937007874 mil |
| 2.5 µm | 0.09842519685 mil |
| 5 µm | 0.1968503937 mil |
| 10 µm | 0.3937007874 mil |
| 20 µm | 0.7874015748 mil |
| 25 µm | 0.9842519685 mil |
| 50 µm | 1.968503937 mil |
| 75 µm | 2.952755906 mil |
| 100 µm | 3.937007874 mil |
| 150 µm | 5.905511811 mil |
| 200 µm | 7.874015748 mil |
| 500 µm | 19.68503937 mil |
| 1000 µm | 39.37007874 mil |
Where it's used
Micrometers are used for particle and filter ratings (PM2.5, PM10, HEPA tested at 0.3 µm), while mils appear in plastic film and bag thickness. Both measure length and distance, so the conversion is a fixed factor.
Micrometer to other length units
| Conversion | 1 µm equals |
|---|---|
| micrometer to meter | 0.000001 m |
| micrometer to kilometer | 1 × 10⁻⁹ km |
| micrometer to centimeter | 0.0001 cm |
| micrometer to millimeter | 0.001 mm |
| micrometer to nanometer | 1000 nm |
| micrometer to angstrom | 10000 Å |
| micrometer to mile | 6.213711922 × 10⁻¹⁰ mi |
| micrometer to yard | 0.000001093613298 yd |
| micrometer to foot | 0.000003280839895 ft |
| micrometer to inch | 0.00003937007874 in |
| micrometer to mil | 0.03937007874 mil |
| micrometer to nautical mile | 5.399568035 × 10⁻¹⁰ nmi |
Frequently asked questions
How many mils are in 1 micrometer?
1 µm = 0.03937007874 mil.
How do I convert micrometers to mils?
Multiply the value in µm by 0.03937007874, or divide it by 25.4. For example, 15 µm × 0.03937007874 = 0.5905511811 mil.
Is the µm to mil conversion exact?
Yes. Both units are defined exactly, so the ratio is exact; its decimal form does not terminate and is shown here to 10 significant figures (more with the precision selector).
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "mil (0.001 in)".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Micrometers to Mils. Retrieved October 17, 2026, from https://scientificconverters.com/length/micrometers-to-mils/
IEEE
Scientific Converters, "Convert Micrometers to Mils," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/length/micrometers-to-mils/