A rotary impact tool includes a housing, an electric motor, and a drive assembly for converting a continuous torque input from the motor to consecutive rotational impacts upon a workpiece. An anvil has a bore defining a hexagonal cross-sectional shape and having a nominal width of 7/16 inches. A hammer is rotationally and axially movable relative to the anvil for imparting the consecutive rotational impacts upon the anvil. A spring biases the hammer in an axial direction toward the anvil. A battery pack has a nominal voltage of at least 18 Volts and a nominal capacity of at least 5 Ah. The rotary impact tool has an overall weight including the battery pack that is less than or equal to 7.5 pounds. A second performance ratio of the rotary impact tool, defined as (ηa×RPMno-load/Inertiahammer)×(1/216,000,000) is greater than 2.