AWG 31 Wire

Diameter 0.0089″
Millimeters 0.226 mm
Cross-section 79 cmil
mm² 0.0401

Nominal bare-conductor dimensions per ASTM B258. AWG is geometric: d = 0.005 × 92(36−n)/39 in with n = 31; area is derived from the diameter. Ampacity depends on insulation, bundling, and the electrical code in force — it is a property of the installation, not the gauge.

Neighboring gauges

AWG Diameter mm vs AWG 31
29 0.0113″ 0.287 +0.0024″
30 0.0100″ 0.254 +0.0011″
31 0.0089″ 0.226
32 0.0080″ 0.203 −0.0009″
33 0.0071″ 0.180 −0.0018″
Data provenance. ASTM B258, Standard Specification for Nominal Diameters of AWG Sizes (ASTM International). See all data sources.