What is the standard size of wall plate?

The standard size of a wall plate, also known as an outlet cover or switch plate, typically measures 4.5 inches tall by 2.75 inches wide for single-gang plates. For double-gang plates, the standard dimensions are approximately 4.5 inches tall by 5.25 inches wide. However, variations exist for specialty plates, such as those for multiple outlets or custom designs. Always check specific product specifications for exact measurements.