Benjamin Géza Affleck-Boldt was born in Berkeley, California.

Affleck grew up in Cambridge, Massachusetts, with a mother who was a school district employee and teacher, and a father who worked in various roles including drug counselor, social worker, and actor.

Affleck starred in the PBS educational series "The Voyage of the Mimi".

Affleck briefly attended the University of Vermont and Occidental College but left before graduating to focus on acting.