Divide mils by 1,000 to get inches. Plastic sheeting sold as “6 mil” is 0.006 inches thick.
How to use the Mil to Inch Converter
- Type the number of mils into the Mils field. Decimals such as 500 are fine.
- Read the answer in Inches – it updates as you type, with no button to press.
- To convert the other way, type into Inches and the mils are recalculated.
- Press Copy results to copy both values with the page title, or Copy link to share this exact conversion.
This page converts only mil ⇄ in. Need a different unit? Use the general length converter, where you can choose any “from” and “to” unit.
How it works
Both units measure length, so they are always in the same ratio: one mil (thou) equals 0.001 inches. The calculator multiplies the number of mils you type by 0.001 to give inches, and when you type into the inches field it divides by the same factor to give mils. Because the ratio never changes, doubling the mils always doubles the inches. Results are calculated at full precision and rounded only for display (up to eight decimal places, with very large or small values shown in scientific notation).
How to convert mils to inches
- Write down the value in mils, for example 1,000 mil.
- Multiply by the conversion factor 0.001 (because 1 mil (thou) = 0.001 in).
- 1,000 × 0.001 = 1 in.
- To go back from inches to mils, divide by 0.001 – or multiply by 1,000.
mil to in conversion table
| Mils | Inches | Inches | Mils |
|---|---|---|---|
| 1 mil | 0.001 in | 1 in | 1000 mil |
| 2 mil | 0.002 in | 2 in | 2,000 mil |
| 3 mil | 0.003 in | 5 in | 5,000 mil |
| 4 mil | 0.004 in | 10 in | 10,000 mil |
| 6 mil | 0.006 in | 20 in | 20,000 mil |
| 8 mil | 0.008 in | 50 in | 50,000 mil |
| 10 mil | 0.01 in | 100 in | 100,000 mil |
| 20 mil | 0.02 in | 1,000 in | 1,000,000 mil |
| 40 mil | 0.04 in | ||
| 100 mil | 0.1 in | ||
| 1,000 mil | 1 in |
What is a mil?
A mil (or thou) is one thousandth of an inch, 25.4 µm. It is used in North America for plastic film, garbage bags, paint and coating thickness and circuit-board traces; it is not a millimetre.
What is an inch?
The inch has been defined as exactly 25.4 mm since 1959. It is used in the U.S. for almost everything and worldwide for screen sizes, wheel and tyre sizes, pipe threads and many tools.
Common mistakes to avoid
Mixing the international foot (0.3048 m) with the old u.s. survey foot, confusing nautical and statute miles, and writing decimal feet such as 5.5 ft as “5 ft 5 in” (it is 5 ft 6 in).
Formula
1 mil = 0.001 in1 in = 1,000 milin = mil × 0.001Worked example
Inputs — Mils: 1,000 mil.
Results — Inches = 1 in.
Frequently asked questions
How many inches is 6 mil?
0.006 in.
Is a mil a millimetre?
No; 1 mil = 0.0254 mm.
How do I convert mils to inches?
Multiply the number of mils by 0.001. For example, 1,000 mil × 0.001 = 1 in.
How do I convert inches back to mils?
Divide by 0.001 (or multiply by 1,000), or simply type the value into the inches field above.
What is 10 mil in inches?
10 mil = 0.01 in.
What is 100 mil in inches?
100 mil = 0.1 in.
Is this conversion exact?
Yes. The factor comes from the official definitions of both units (NIST and the SI), so the only difference you may see is rounding in the last displayed digit.
Can I convert to other units on this page?
This page converts only between mils and inches. To pick any length unit, use the general length converter linked under Related calculators.
What formula does the Mil to Inch Converter use?
1 mil = 0.001 in.