Kat then explained that she got the idea to change her name after visiting with a family friend, children's fantasy author Lloyd Alexander. “Randomly, he was my mother’s best friend,” she said.

Dennings said she has used “all kinds of nicknames” for her real first name, Katherine, and explained that she landed on Kat as her official first name thanks to the 1995 movie “Casper.” ...

Kat Dennings reveals her real name — and why she changed it — on Kylie Kelce’s podcast "I was like, ‘This can’t be displayed on a poster.’” March 14, 2025, 8:46 AM PDT / Source: TODAY ...

Dennings returned to the sitcom world in the early 2010s, starring opposite Beth Behrs on the CBS workplace comedy "2 Broke Girls." The Emmy-winning series ran for six seasons from 2011 to 2017.