Convert between mils and inches in either direction.
How it works
A mil is exactly one-thousandth of an inch by definition, so 1 mil = 0.001 in. Enter a value in either field and the other updates instantly.
What this does not include
This is the “mil” meaning a thousandth of an inch, distinct from this site’s mil-to-mm converter, which converts the same unit into a metric length rather than back into inches.
How to use this calculator
- Enter a value in mils or inches.
- The other field updates automatically.
Why express something in mils instead of a fraction of an inch?
Decimal mils are easier to work with in precision manufacturing than fractions like 1/64 inch, especially for very thin materials like wire coatings and plastic film.
How many mils are in a full inch?
Exactly 1,000 mils make one inch, following directly from the definition of a mil as a thousandth of an inch.
Is a mil the same everywhere it’s used?
Yes, within the “thousandth of an inch” meaning used in the US — but be aware “mil” is also sometimes used informally to mean “millimeter,” a completely different and much larger unit, so context matters.
