Length · Unit Converter

Convert Square Chain to Square Mil

Convert square chains to square mils instantly. 1 square chain = 6.27264e+11 square mil — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Mil to Square 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

Square Chain

What is a square chain?

A square chain is an imperial unit of area equal to approximately 404.686 m². It equals 1/10 of an acre.

Origin of the square chain

Derived by squaring the chain (66 feet or 22 yards). The chain was defined by Edmund Gunter in 1620 specifically so that 10 square chains equal exactly one acre.

Where it is used

Square chains appear in US Public Land Survey System (PLSS) records and historical English property documents. The 10-to-1 ratio with acres made early survey arithmetic easier.

When and where it was developed

Defined by Edmund Gunter in 1620 specifically for surveying convenience.

Imperial / US Customary

Square Mil

What is a square mil?

A square mil is an imperial unit of area equal to 6.4516×10⁻¹⁰ m². It is widely used in printed circuit board (PCB) design and electronics manufacturing.

Origin of the square mil

Derived by squaring the mil (1 mil = 1/1000 of an inch = 0.0254 mm). Standardized via the 1959 International Yard and Pound Agreement.

Where it is used

Square mils are the standard unit for PCB trace cross-sections, pad areas, and component pitches in US-localized electronic design software and datasheets.

When and where it was developed

Standardized via the 1959 International Yard and Pound Agreement.

Square Chain to Square Mil conversion formula

The relationship between square chains and square mils:

1 ch² = 6.27264e+11 mil²
1 mil² = 1.594225e-12 ch²

To convert square chains to square mils, multiply the value in square chains by 6.27264e+11. To reverse, multiply square mils by 1.594225e-12.

How to use this converter

Type a value into the calculator. The result in square 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 Square Mil to Square Chain converter for the reverse direction.

Step-by-step: convert square chains to square mils

  1. Write down the value in square chains (ch²).
  2. Multiply that value by the factor 6.27264e+11.
  3. The product is the equivalent value in square mils (mil²).
  4. To reverse, multiply the square mil value by 1.594225e-12.

Worked examples

Example 1 — Convert 1 ch² to mil²:
1 × 6.27264e+11 = 6.27264e+11 mil²

Example 2 — Convert 100 ch² to mil²:
100 × 6.27264e+11 = 6.27264e+13 mil²

Square Chain to Square Mil conversion table

Standard reference values for converting square chains to square mils:

Square Chain [ch²]Square Mil [mil²]
0.016.27264e+9
0.16.27264e+10
16.27264e+11
21.254528e+12
31.881792e+12
42.509056e+12
53.13632e+12
106.27264e+12
201.254528e+13
301.881792e+13
402.509056e+13
503.13632e+13
1006.27264e+13
5003.13632e+14
10006.27264e+14

Frequently asked questions

How many square mils is 1 square chain?
1 square chain equals 6.27264e+11 square mil.
How do I convert square chains to square mils?
Multiply the value in square chains by 6.27264e+11 to get square mils.
How do I convert square mils back to square chains?
Multiply the value in square mils by 1.594225e-12, or use the Square Mil to Square Chain converter.
How many square mils is 100 square chains?
100 square chains equals 6.27264e+13 square mils, because 100 × 6.27264e+11 = 6.27264e+13.

Convert Square Chain to other area units

Show all Square Chain conversions

Sources & references

Conversion factor (1 ch² = 6.27264e+11 mil²) verified against the following authoritative sources:

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