Convert Circular Mils to Square Rods
Convert Circular Mils (cmil) to Square Rods (sq rd) instantly and accurately.
Conversion Formula
sq rd = cmil × 2.003362319e-11
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 Rods
A square rod (sq rd), also called a perch or square pole, equals the area of a square with sides of one rod (5.0292 m or 16.5 ft), giving approximately 25.29 m². This traditional unit was central to land surveying before the adoption of the metric system and remains embedded in legal property descriptions in the United States. There are exactly 160 square rods in one acre, and 40 square rods in one rood. Old farmland deeds and archaic land records in the UK and US frequently reference perches and square rods.
Quick Reference Table
| Circular Mils (cmil) | Square Rods (sq rd) |
|---|---|
| 1 cmil | 2.003 × 10-11 sq rd |
| 2 cmil | 4.007 × 10-11 sq rd |
| 5 cmil | 1.002 × 10-10 sq rd |
| 10 cmil | 2.003 × 10-10 sq rd |
| 25 cmil | 5.008 × 10-10 sq rd |
| 50 cmil | 1.002 × 10-9 sq rd |
| 100 cmil | 2.003 × 10-9 sq rd |