List of Famous people who are 21

Steven Weisberg is a film editor who usually collaborates with director Alfonso Cuarón

Ángel Jeremy Márquez Castañeda is a Mexican professional footballer who plays as a midfielder for Liga MX club Atlas.

Cynthia Ettinger is an American actress, known for her stage and television work, most notably her appearances on the TV series Carnivàle and in the unaired pilot of the TV series Smallville.

Liu Xuanxuan is a Chinese badminton player from Hunan. She was part of the national junior team that won the mixed team title at the 2017 and 2018 World Junior Championships and also at the 2018 Asian Junior Championships. Liu won her first senior international title at the 2018 Lingshui China Masters in the mixed doubles event partnered with Guo Xinwa.

Michael J. Horton is a film editor who works primarily in New Zealand. He was nominated for an Academy Award for the 2002 film The Lord of the Rings: The Two Towers that was directed by Peter Jackson.