List of Famous people who are 21

Donald Brochu is an American film editor.

Gary O'Shaughnessy is an Irish singer and musician who represented Ireland in Eurovision Song Contest 2001 with the song "Without Your Love" finishing 21st out of 23 entries. He's the uncle of Ryan O'Shaughnessy who represented Ireland at the Eurovision Song Contest 2018.

Heather Loeffler is a set decorator. Loeffler, along with production designer Judy Becker, is nominated for an Academy Award for Best Production Design for the 2013 film American Hustle.

Jeremy Theobald is a British actor best known for his portrayal of "The Young Man", the main character in Christopher Nolan's 1998 major picture debut Following, and for which Theobald was also a producer. Filming was scheduled around their day jobs. Jonathan Romney, writing in the New Statesman, noted that "Nolan and his cast are terrific finds: I wouldn't normally say this to struggling artists, but they might want to give up their day jobs."