Dexter, of Dexter's Laboratory, is a small red-haired boy who is a scientific genius. At only 6 years old, Dexter speaks with an accent that only a middle-aged Austrian man would tote. He typically wears thick-rimmed black glasses, black slacks, a white lab coat, and purple latex gloves. He has one older sister, DeeDee, and is otherwise a member of a typical nuclear family. His arch nemesis is Mandark, lard of dorkness.

Dexter is alone in the world, with only science to keep him company. He creates robots and intelligent machines so that he does not become stupid, a state thoroughly feared by Dexter. He loves school, and is the teacher's pet until Mandark enters the scene. His sister is constantly ruining his scientific endeavors, and so Dexter is always on the run.

Gennedy Tartakovsky is credited with creating Dexter's lab. He developed DeeDee first, and then went on to create Dexter, her ultimate opposite. A dancing DeeDee was the 1991 animation project that spawned Dexter's existence. Since then, Dexter's Laboratory has been produced as both cartoons and comic books by Cartoon Network.

Recently, Dexter appeared in the Macy's Thanksgiving Day Parade. He was the largest inflatable man at the event.