How is the size of an electric drill usually determined?

The size of an electric drill is typically determined by its drill chuck capacity. This capacity indicates the range of drill bit sizes that the chuck can accommodate, which is essential for understanding what types of tasks the drill can perform. For instance, a drill chuck with a larger capacity can hold larger bits, allowing for a wider variety of drilling applications.

While other factors, such as current rating, physical size, and motor size, can influence a drill's performance, they do not directly define the size of the drill in the same way the chuck capacity does. Current rating may indicate how much power the drill can use, physical size can refer to the overall dimensions of the drill, and motor size may relate to the torque produced, but these aspects ultimately do not determine the specific drill bit sizes the tool can accommodate. Thus, focusing on the drill chuck capacity provides the most accurate measure of the drill's versatility and application range.