Find the right wire size for any circuit. AWG & metric charts with ampacity, resistance, and diameter. Based on NEC and IEC standards.
All wire data calculated from the AWG formula (ASTM B258), material resistivities, and NEC/IEC ampacity standards.
Every AWG size from 4/0 to 40, all 19 IEC metric sizes, 8 conductor materials, and NEC ampacity at 60/75/90°C.
Appliance wiring guides with NEC references, breaker sizes, and wire types. Real-world sizing for dryers, hot tubs, EV chargers, and more.