What the standard defines
AWG numbers a conductor by how many drawing steps produced it, so the number rises as the wire gets thinner. The metric scale states the cross-sectional area directly in square millimetres. Both describe the amount of copper available to carry current, and both are published on cable and in the specifications of terminals, ferrules and connectors.
IEC 60228 additionally defines conductor classes — solid, stranded, flexible, extra-flexible — which decide how a cable bends and how it behaves in a crimp, independently of its area.
What it does not promise
Neither scale states a current rating on its own. What a conductor may carry depends on the insulation temperature, the ambient temperature, whether the cable is bundled or in free air, and the acceptable voltage drop over the run — which on a 12 V system is usually the binding constraint rather than heating.
A conversion between the two scales is also approximate. The AWG steps do not fall on the metric sizes, so a listing that prints “6 mm² (10 AWG)” is rounding in one direction or the other.
What it works with
Cable size decides which lug, which ferrule and which crimping die fit, which terminal will close, and what a busbar stud accepts. On this site it appears wherever current is carried: battery leads, solar runs, extension cables and the tools that terminate them.
What people ask before they order
Is 10 AWG the same as 6 mm²?
Close, not equal: 10 AWG is about 5.26 mm². Listings that print both are rounding, and the honest ones say so. Where a maker specifies a minimum, this site reports the figure and the unit the maker used.
Why does a bigger number mean a thinner wire in AWG?
Because the gauge counts drawing operations: the more times a wire was drawn, the thinner it is and the higher the number. It is a manufacturing scale rather than a measurement.
Last reviewed 16 September 2026