Convert Circular Mils to Square Micrometers
Convert Circular Mils (cmil) to Square Micrometers (μm²) instantly and accurately.
Conversion Formula
μm² = cmil × 506.7074791
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 Micrometers
A square micrometer (μm²), also called a square micron, equals one trillionth of a square meter - the area of a square with sides one millionth of a meter (10⁻¹² m²). This is the natural scale of biological cells: a human red blood cell has a surface area of about 135 μm², and a typical bacterium might occupy 2-10 μm². Square micrometers are the standard unit in cell biology, histology, microscopy, and semiconductor characterisation where individual features on wafers are measured.
Quick Reference Table
| Circular Mils (cmil) | Square Micrometers (μm²) |
|---|---|
| 1 cmil | 506.707 μm² |
| 2 cmil | 1013.41 μm² |
| 5 cmil | 2533.54 μm² |
| 10 cmil | 5067.07 μm² |
| 25 cmil | 12667.7 μm² |
| 50 cmil | 25335.4 μm² |
| 100 cmil | 50670.7 μm² |