Electricians

Wire Size Quick Reference

Amperage to minimum wire gauge for copper. Residential and commercial use cases.

Wire Size Calculator
1A50A100A150A200A
Minimum Wire Size (Copper, 75\u00B0C)
12 AWG
Rated for 20A | Kitchen, bathroom, laundry outlets
Quick Reference (Copper, 75\u00B0C)
14 AWG15ALighting circuits, general outlets
12 AWG20AKitchen, bathroom, laundry outlets
10 AWG30ADryers, water heaters, A/C units
8 AWG40ARanges, large appliances
6 AWG55ALarge A/C, sub-panels
4 AWG70AFeeders, sub-panels
3 AWG85AFeeders, service entrance
2 AWG95AFeeders, large sub-panels
1 AWG110AService entrance, feeders
1/0 AWG125AService entrance, feeders
2/0 AWG145AService entrance
3/0 AWG165A200A residential service
4/0 AWG195A200A service, large feeders
Based on NEC Table 310.16 (simplified)
Copper conductors, 75\u00B0C rating
20A load \u2192 minimum 12 AWG (20A rated)
Precision disclaimer: This is a simplified reference based on NEC Table 310.16 for copper at 75\u00B0C. Actual wire sizing must account for derating factors, ambient temperature, conduit fill, voltage drop, and other NEC requirements. Always consult the full NEC and a licensed electrician.

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