AWG to mm² conversion chart and calculator

Because they measure different things by different logic. AWG is a geometric series of drawing-die steps — each gauge is the previous diameter divided by a constant ratio — while metric sizes state the conductor cross-section directly. AWG 20 works out to 0.518 mm², which is why it is commonly paired with the 0.5 mm² metric size rather than equal to it.

No — it is the closest standard size, and the table leaves the column blank where nothing is reasonably close. When a specification demands a minimum cross-section, round up to the next standard metric size rather than taking the nearest; when matching a machine rating, compare against the actual mm² value in the second column.

The table gives the equivalent solid-conductor diameter. A stranded bundle of the same cross-section packs with air gaps between strands, so its outside diameter measures larger, and its insulation OD larger still. Machine specifications on this site state which figure they rate: conductor cross-section (mm² or AWG) for cutting, stripping and crimping, and outer diameter for machines that grip the insulation.

Annealed copper at 20 °C (resistivity 17.24 nΩ·m, the 100% IACS reference), solid conductor. Stranding, plating and temperature all raise it slightly — the column is for sizing sanity checks, not for certified voltage-drop calculations.