Katherine Litwack (born June 13, 1986), better known by the stage name Kat Dennings, is an American actress.
Dennings was born and raised in the Bryn Mawr area near Philadelphia, Pennsylvania. Her mother, Ellie Judith Litwack, is a poet and speech therapist, and her father, Gerald J. Litwack, is a molecular pharmacologist and the chair of the Basic Sciences department of The Commonwealth Medical College in Scranton, Pennsylvania. Dennings is the youngest of five children, including an older brother, Geoffrey S. Litwack. Her family is Jewish.
Dennings was home schooled; her only enrollment at a traditional school was for a half-day at Friends' Central School. She graduated from high school early, at the age of 14. She moved with her family to Los Angeles, California around 2002 so that she could act full time. She adopted the name Dennings as her professional name when she was younger. According to Dennings, as stated in Interview magazine in 2007, her parents initially considered her idea of pursuing an acting career to be "the worst idea ever".