Length · Unit Converter

Convert Ell to Mil

Convert ells to mils instantly. 1 ell = 45000 mil — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Mil to Ell 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

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.

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".

Ell to Mil conversion formula

The relationship between ells and mils:

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

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

How to use this converter

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

Step-by-step: convert ells to mils

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

Worked examples

Example 1 — Convert 1 ell to mil:
1 × 45000 = 45000 mil

Example 2 — Convert 100 ell to mil:
100 × 45000 = 4500000 mil

Real-world example — Macro-to-micro scale comparison

2 ells of measurement converts to a very large number in mils — useful in materials science when comparing bulk-sample dimensions to feature-level surface specs.

2 ell × 45000 = 90000 mil

Real-world example — Macroscopic to microscopic

One ell equals a million mils. Optical engineers calculating coherence length compare macro-scale path lengths with micro-scale wavelength differences using exactly this conversion.

1 ell × 45000 = 45000 mil

Real-world example — Sub-meter precision

A 0.001-ell (1 mm) tolerance equals 1,000 mils — useful for surface-finish specs, where macro-scale dimensions are given in the larger unit but feature roughness in the smaller.

0.001 ell × 45000 = 45 mil

Ell to Mil conversion table

Standard reference values for converting ells to mils:

Ell [ell]Mil [mil]
0.01450
0.14500
145000
290000
3135000
4180000
5225000
10450000
20900000
301350000
401800000
502250000
1004500000
5002.25e+7
10004.5e+7

Frequently asked questions

How many mils is 1 ell?
1 ell equals 45000 mil.
How do I convert ells to mils?
Multiply the value in ells by 45000 to get mils.
How do I convert mils back to ells?
Multiply the value in mils by 2.222222e-5, or use the Mil to Ell converter.
How many mils is 100 ells?
100 ells equals 4500000 mils, because 100 × 45000 = 4500000.

Convert Ell to other length units

Show all Ell conversions

Sources & references

Conversion factor (1 ell = 45000 mil) verified against the following authoritative sources:

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