Ampacity Calculator — Temperature & Bundling Derating | WireStandard

Calculate derated ampacity for copper conductors. Apply NEC temperature correction and bundling derating factors for THWN, THHN, XHHW, NM-B insulation types.

Wire Gauge (AWG)
Insulation Type
Ambient Temperature (°C)
Number of Conductors in Conduit
Derated Ampacity
Base Ampacity
Temp. Correction
Bundling Factor
Installation not permitted

Based on NEC Table 310.12 (copper conductors). Temperature correction per NEC Table 310.15(B)(2)(a). Bundling derating per NEC Table 310.15(C)(1).