Length · Unit Converter

Convert Mil to Ell

Convert mils to ells instantly. 1 mil = 2.222222e-5 ell — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Ell to Mil converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Length category 2 min read Published Last reviewed Updated

Units explained

Imperial / US Customary

Mil

What is a mil?

A mil (also called a thou) is an Imperial unit of length equal to one thousandth of an inch (1/1000 in = 0.0254 mm = 25.4 μm exactly). It is used in engineering, manufacturing, and materials specifications.

Origin of the mil

The mil is derived from the Latin mille, "thousand," denoting one-thousandth of an inch. Standardized in industrial use during the 19th-century rise of precision engineering.

Where it is used

Mils are used to specify thicknesses of plastic films, foils, paper, copper traces on printed circuit boards (PCBs), wire insulation, and paint coatings. A standard sheet of paper is about 4 mils thick.

When and where it was developed

Adopted in 19th-century engineering practice; the value (1/1000 in) became exact in 1959 when the inch was fixed at 25.4 mm via the International Yard and Pound Agreement. The British term is "thou"; American term is "mil".

Imperial / US Customary

Ell

What is a ell?

An ell is an Imperial unit of length equal to 45 inches (1.143 m), historically used as the standard measure of cloth in English commerce.

Origin of the ell

The ell derives from old English elna (forearm) and was standardised in medieval English trade as the cloth-measuring yard equivalent. The English ell is 45 inches; other regional ells differed.

Where it is used

Ells appear in historical English commerce records (especially cloth and tapestry trade). Used in legal documents through the 19th century; rare in modern commerce but referenced in literary and historical contexts.

When and where it was developed

Medieval English cloth-trade origin; standardised at 45 inches; became exact via the 1959 International Yard and Pound Agreement.

Mil to Ell conversion formula

The relationship between mils and ells:

1 mil = 2.222222e-5 ell
1 ell = 45000 mil

To convert mils to ells, multiply the value in mils by 2.222222e-5. To reverse, multiply ells by 45000.

How to use this converter

Type a value into the calculator. The result in ells updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Ell to Mil converter for the reverse direction.

Step-by-step: convert mils to ells

  1. Write down the value in mils (mil).
  2. Multiply that value by the factor 2.222222e-5.
  3. The product is the equivalent value in ells (ell).
  4. To reverse, multiply the ell value by 45000.

Worked examples

Example 1 — Convert 1 mil to ell:
1 × 2.222222e-5 = 2.222222e-5 ell

Example 2 — Convert 100 mil to ell:
100 × 2.222222e-5 = 0.0022222222 ell

Real-world example — Macro-scale buildup

A million mils equals exactly one ell — the conversion that bridges microscale features and macroscale objects in microfluidic, biomedical, and semiconductor packaging design.

1000000 mil × 2.222222e-5 = 22.2222222222 ell

Real-world example — Quarter-meter measurement reference

A 250,000-mil length equals 0.25 ells — useful for comparing supply-chain spec sheets where some lengths are quoted in the smaller unit and some in the larger.

250000 mil × 2.222222e-5 = 5.5555555556 ell

Real-world example — From microscopic to macroscopic

A million mils equals exactly one ell. This kind of conversion appears in microfluidics, where total channel length is given in ells but feature widths are in mils.

1000000 mil × 2.222222e-5 = 22.2222222222 ell

Mil to Ell conversion table

Standard reference values for converting mils to ells:

Mil [mil]Ell [ell]
0.012.222222e-7
0.12.222222e-6
12.222222e-5
24.444444e-5
36.666667e-5
48.888889e-5
50.0001111111
100.0002222222
200.0004444444
300.0006666667
400.0008888889
500.0011111111
1000.0022222222
5000.0111111111
10000.0222222222

Frequently asked questions

How many ells is 1 mil?
1 mil equals 2.222222e-5 ell.
How do I convert mils to ells?
Multiply the value in mils by 2.222222e-5 to get ells.
How do I convert ells back to mils?
Multiply the value in ells by 45000, or use the Ell to Mil converter.
How many ells is 100 mils?
100 mils equals 0.0022222222 ells, because 100 × 2.222222e-5 = 0.0022222222.

Convert Mil to other length units

Show all Mil conversions

Sources & references

Conversion factor (1 mil = 2.222222e-5 ell) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.