American wire gauge

American wire gauge (AWG) is a standard wire gauge system used predominantly in the United States and Canada for the diameters of a single non-ferrous, solid, round conductor. Increasing gauge numbers give decreasing wire diameters.

Single core and stranded
The cross-sectional area of each gauge is an important factor for determining its current-carrying capacity and resistance. The AWG of a stranded wire is determined by the total cross-sectional area of the conductor. Because there are also small gaps between the strands, a stranded wire will be about 5% thicker than a solid wire with the same AWG.