Convert Circular Mils to Square Miles

Convert Circular Mils (cmil) to Square Miles (mi²) instantly and accurately.

Circular Mils (cmil)
Square Miles (mi²)

Conversion Formula

mi² = cmil × 1.956408514e-16

About Circular Mils

A circular mil (cmil) is a unit used in electrical engineering to specify the cross-sectional area of round wires and cables. Equal to the area of a circle with a diameter of exactly one thou (one thousandth of an inch) - approximately 5.067 × 10⁻¹⁰ m² - it simplifies wire calculations: the cross-sectional area in cmil equals the wire diameter in mils, squared. US electrical codes (NEC/NEMA) specify conductor sizes in circular mils, and large cables are rated in thousands of circular mils (kcmil or MCM). A 12 AWG wire, common in US household wiring, has a cross-section of 6,530 cmil.

About Square Miles

A square mile (mi²) is an imperial unit of area equal to a square with sides of one mile (5,280 ft × 5,280 ft). It is used for measuring large land areas like counties, states, and countries in the United States. Los Angeles covers about 503 mi², Rhode Island (smallest US state) is roughly 1,214 mi², and Alaska is about 665,384 mi². This unit is standard in American geography, land surveying, and regional planning.

Quick Reference Table

Circular Mils (cmil)Square Miles (mi²)
1 cmil1.956 × 10-16 mi²
2 cmil3.913 × 10-16 mi²
5 cmil9.782 × 10-16 mi²
10 cmil1.956 × 10-15 mi²
25 cmil4.891 × 10-15 mi²
50 cmil9.782 × 10-15 mi²
100 cmil1.956 × 10-14 mi²

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