circular mil
Areaexact by definition
A circular mil is the area of a circle one thou (0.001 in) in diameter, about 5.067 × 10⁻¹⁰ m². Its virtue is that a round conductor's area in circular mils is simply its diameter in thou, squared, with no π to carry: a 100 thou wire is 10,000 cmil.
Watch out: The factor involves π, so it is exact by definition but not a terminating decimal. Do not confuse the circular mil with the square mil, which is π/4 times larger and is what you get if you square the diameter without thinking about the shape.
| 1 | 5.0670748e-10 |
Where the unit came from
The unit exists because wire is specified by diameter and sold by cross section, and before calculators the squaring shortcut was worth a great deal. American Wire Gauge tables are still published with a circular mil column.
One circular mil in every area unit
| 5.06707e+24 | microbarn (μb) | |
| 5.06707e+21 | millibarn (mb) | |
| 5.06707e+18 | barn (b) | |
| 506,707,000 | square nanometer (nm²) | |
| 506.707 | square micrometer (μm²) | |
| 1 | circular mil (cmil)this unit | |
| 0.001 | thousand circular mils (kcmil) | |
| 0.000506707 | square millimeter (mm²) | |
| 0.00000506707 | square centimeter (cm²) | |
| 7.85398e-07 | square inch (in²) | |
| 5.06707e-08 | square decimeter (dm²) | |
| 5.45415e-09 | square foot (ft²) | |
| 6.06017e-10 | square yard (yd²) | |
| 5.06707e-10 | square meter (m²) | |
| 1.53279e-10 | tsubo (tsubo) | |
| 2.00336e-11 | square rod (rd²) | |
| 5.06707e-12 | are (a) | |
| 1.25210e-12 | square chain (ch²) | |
| 5.06707e-13 | dunam (dunam) | |
| 5.00841e-13 | rood (rood) | |
| 1.25210e-13 | acre (ac) | |
| 5.06707e-14 | hectare (ha) | |
| 5.06707e-16 | square kilometer (km²) | |
| 1.95641e-16 | square mile (mi²) |
Solvers that use area