Convert Square Chains to Square Millimeters

Convert Square Chains (ch²) to Square Millimeters (mm²) instantly and accurately.

Square Chains (ch²)
Square Millimeters (mm²)

Conversion Formula

mm² = ch² × 404685642.2

About Square Chains

A square chain (ch²) is a surveying unit equal to the area of a square with sides of one Gunter's chain (66 feet or ~20.12 m), approximately 404.69 m². Ten square chains equal exactly one acre, making it the natural subdivision unit in traditional land surveying. The US Public Land Survey System used chains to lay out townships and sections, and square chains appear throughout old legal property descriptions and government land grants across North America. One square chain equals exactly 16 square rods.

About Square Millimeters

A square millimeter (mm²) is a metric unit of area equal to a square with sides of one millimeter. It is commonly used in precision engineering, electronics, and measuring very small surfaces such as microchips or printed circuit boards. To visualise: a typical pinhead has an area of about 2-3 mm². This unit is essential in microscopy, medical imaging, and manufacturing where tiny, precise measurements are critical.

Quick Reference Table

Square Chains (ch²)Square Millimeters (mm²)
1 ch²404686000 mm²
2 ch²809371000 mm²
5 ch²2.023 × 109 mm²
10 ch²4.047 × 109 mm²
25 ch²1.012 × 1010 mm²
50 ch²2.023 × 1010 mm²
100 ch²4.047 × 1010 mm²

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