6 AWG (American Wire Gauge) wire specifications: 4.1154 mm diameter, 13.3018 mm² area, 65A ampacity (copper, 75°C). Resistance, weight, and common uses.
| Diameter | 4.1154 mm · 0.162023" · 162.02 mils |
| Cross-sectional area | 13.3018 mm² · 26,251 circular mils |
| Resistance (copper, 20°C) | 1.2961 Ω/km · 0.395 Ω/1000ft |
| Resistance (aluminum, 20°C) | 2.1248 Ω/km · 0.6476 Ω/1000ft |
| Ampacity — copper 60°C | 55 A |
| Ampacity — copper 75°C | 65 A |
| Ampacity — copper 90°C | 75 A |
| Ampacity — aluminum 75°C | 50 A |
| Weight (copper) | 119.184 kg/km · 80.088 lbs/1000ft |
| Weight (aluminum) | 35.915 kg/km · 24.134 lbs/1000ft |
| Closest IEC 60228 size | 16 mm² |
| Skin depth at 60 Hz | 8.531 mm |
| Type | Temperature | Description |
|---|---|---|
| THHN/THWN-2 | 90°C dry / 75°C wet | Most common for building wire |
| XHHW-2 | 90°C dry and wet | Cross-linked polyethylene, moisture resistant |
| USE-2 | 90°C | Underground service entrance |
| NM-B (Romex) | 90°C | Non-metallic sheathed cable for residential |
| UF-B | 60°C | Underground feeder, direct burial |
6 AWG copper is commonly used for 50–60A circuits such as ranges, hot tubs and EV chargers. NEC Table 310.16 rates it 65A at 75°C. It measures 4.115 mm in diameter with a 13.3 mm² cross-section.
Per NEC Table 310.16 (30°C ambient, no more than three current-carrying conductors), 6 AWG copper is rated 55A at 60°C, 65A at 75°C and 75A at 90°C. 6 AWG aluminum is rated 40A, 50A and 55A in the same columns. On circuits of 100A or less, NEC 110.14(C) generally requires the 60°C column unless every termination is rated 75°C.
Yes. 6 AWG aluminum is rated 50A at 75°C versus 65A for copper, so matching the copper rating takes 4 AWG aluminum. Aluminum at this size is common for feeders, subpanels and service conductors (SER, USE-2, XHHW-2). Use AL-rated lugs, torque to the manufacturer’s spec and apply antioxidant compound where required.