Length · Unit Converter

Convert Chain to Mil

Convert chains to mils instantly. 1 chain = 792000 mil — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Mil to Chain 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

Chain

What is a chain?

A chain is an Imperial unit of length equal to 66 feet (20.1168 m), or exactly 4 rods or 100 links. It is the central unit in the Gunter chain-based land-survey system.

Origin of the chain

Defined by Edmund Gunter in 1620 specifically to make land-area arithmetic easy: 10 square chains = 1 acre exactly. The 66-foot length and 100-link subdivision were chosen so chain measurements could be added decimally.

Where it is used

Chains are the fundamental unit of legacy US public land surveys (the entire US township-and-range system uses chains). Modern survey work generally uses meters or feet, but legacy deeds remain in chains.

When and where it was developed

Invented by Edmund Gunter in 1620; standardised throughout English and American land survey; 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".

Chain to Mil conversion formula

The relationship between chains and mils:

1 ch = 792000 mil
1 mil = 1.262626e-6 ch

To convert chains to mils, multiply the value in chains by 792000. To reverse, multiply mils by 1.262626e-6.

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 Chain converter for the reverse direction.

Step-by-step: convert chains to mils

  1. Write down the value in chains (ch).
  2. Multiply that value by the factor 792000.
  3. The product is the equivalent value in mils (mil).
  4. To reverse, multiply the mil value by 1.262626e-6.

Worked examples

Example 1 — Convert 1 ch to mil:
1 × 792000 = 792000 mil

Example 2 — Convert 100 ch to mil:
100 × 792000 = 7.92e+7 mil

Chain to Mil conversion table

Standard reference values for converting chains to mils:

Chain [ch]Mil [mil]
0.017920
0.179200
1792000
21584000
32376000
43168000
53960000
107920000
201.584e+7
302.376e+7
403.168e+7
503.96e+7
1007.92e+7
5003.96e+8
10007.92e+8

Frequently asked questions

How many mils is 1 chain?
1 chain equals 792000 mil.
How do I convert chains to mils?
Multiply the value in chains by 792000 to get mils.
How do I convert mils back to chains?
Multiply the value in mils by 1.262626e-6, or use the Mil to Chain converter.
How many mils is 100 chains?
100 chains equals 7.92e+7 mils, because 100 × 792000 = 7.92e+7.

Convert Chain to other length units

Show all Chain conversions

Sources & references

Conversion factor (1 ch = 792000 mil) verified against the following authoritative sources:

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