What Size Wire for an Air Compressor?
Wire and breaker sizing for an Air Compressor — the typical 240V circuit, plus the code details (NEC 310.16) that change the answer.
Calculations are built on the 2023 National Electrical Code (NEC) and cross-checked against the published code tables. How we verify. Last reviewed June 2026.
On a 30A 240V circuit at 75°C terminations.
Protected by a 30A breaker (NEC 240.6).
Air Compressor current varies by model. The size above is the common case — always size the conductor to the unit’s nameplate rating and protect it at the labeled maximum breaker/fuse.
Air Compressor Circuit Details
- Size to the motor FLA × 125%. A 240V 3–5 HP compressor typically needs a 30A circuit (10 AWG).
- Hard-starting motors benefit from a dedicated circuit to avoid voltage sag.
- Confirm 120V vs 240V — many shop compressors are convertible.
Long run to your air compressor?
Over distance, voltage drop can require a larger wire than the table above. See the 30A wire size by distance:
Size it for your exact install
Open the calculator pre-filled with 30A at 240V to add distance, material and temperature.