What is the minimum wire size required for a 20 amp circuit?

The minimum wire size required for a 20 amp circuit is indeed 12 AWG. This gauge is commonly accepted for protecting 20 amp circuits because it can safely carry the electrical current without overheating. The National Electrical Code (NEC) stipulates certain wire gauges for specific applications based on the amount of current they need to handle, and 12 AWG wire is rated for up to 20 amps in residential applications.

Using 12 AWG wire for a 20 amp circuit helps ensure safety and efficiency, allowing for the appropriate voltage drop and ensuring the circuit breaker functions correctly in case of overload. This is critical for preventing wires from overheating, which could lead to fire hazards.

Larger wire sizes, such as 10 AWG, are typically reserved for circuits carrying higher currents, while wire sizes smaller than 12 AWG, like 14 AWG or 16 AWG, do not suffice for a 20 amp load. Such smaller gauges would likely overheat and fail when subjected to the current that a 20 amp circuit would carry. Hence, 12 AWG is the minimum wire size that aligns with safety codes and practices for this current rating.