10 gauge wire at a glance
| Diameter (bare copper) | 0.1019 in (2.59 mm) |
|---|---|
| Cross-section area | 5.26 mm² (10,380 circular mils) |
| Copper ampacity, 60°C / 75°C / 90°C | 30 / 35 / 40 A |
| Maximum breaker (copper) | 30 A |
| Aluminum ampacity, 60°C / 75°C / 90°C | 25 / 30 / 35 A |
14 AWG copper is limited to 15 A, 12 AWG to 20 A and 10 AWG to 30 A, and 12 and 10 AWG aluminum to 15 A and 25 A, by the overcurrent rules in NEC 240.4(D), even where the ampacity table lists more.
How far can 10 gauge wire run?
Current is only half the story. The wire loses voltage over distance, and the NEC recommends staying within 3%. This table gives the longest one-way run of 10 AWG copper within 3% drop, by current and voltage.
| Current | 12 V DC | 24 V DC | 120 V AC | 240 V AC |
|---|---|---|---|---|
| 10 A | 14 ft | 29 ft | 145 ft | 290 ft |
| 20 A | 7.2 ft | 14 ft | 72 ft | 145 ft |
| 30 A | 4.8 ft | 9.7 ft | 48 ft | 97 ft |
Use the voltage drop calculator for another size, current or limit. For 12 V runs by size, see the 12V wire gauge chart.
What 10 gauge wire is used for
- Electric dryers, 30 A at 240 V
- Electric water heaters and small AC condensers
- RV 30 A shore power and long 20 A runs
Cable type and the rules
10/2 and 10/3 NM-B (Romex) is rated 30 A. Aluminum 10 AWG is limited to a 25 A breaker.
Neighboring sizes
| Gauge | Diameter | Copper amps (75°C, with NEC 240.4(D) limits) |
|---|---|---|
| 12 AWG | 0.0808 in | 20 A |
| 10 AWG | 0.1019 in | 30 A |
| 8 AWG | 0.1285 in | 50 A |
The wire gauge chart covers every size, and the amps per wire size table lists them in all three temperature columns.
Frequently asked questions
How many amps can 10 gauge wire handle?
30 amps for copper, 25 amps for aluminum, as limited by NEC 240.4(D).
How many watts can 10 gauge wire handle?
3,600 W at 120 V or 7,200 W at 240 V on a 30 A circuit. For a continuous load, use 80%.
What size breaker for 10 gauge wire?
A 30 amp breaker or smaller for copper.
How far can 10 gauge wire run?
About 48 feet at 30 A and 120 V within 3% drop, or about 97 feet at 30 A and 240 V.