Authors born in 1990
- Jon Bellion Singer-Songwriter, 1990
- Jonathan Brownlee Athlete, 1990
- Jonathan Lipnicki Actor, 1990
- Jordan Henderson Football Player, 1990
- Jose Altuve Baseball Player, 1990
- Josh Katz Singer, 1990
- Joss Favela Composer, 1990
- Jourdan Dunn Model, 1990
- Kacy Catanzaro Artistic Gymnast, 1990
- Kane Morgan Athlete, 1990
- Kat Dahlia Composer, 1990
- Kathryn McCormick Dancer, 1990
- Katie Findlay Actress, 1990
- Kay Panabaker Actress, 1990
- Kayla Harrison Judoka, 1990
- Keenon Daequan Ray Jackson Rapper, 1990
- Keisha Castle-Hughes Actress, 1990
- Kelita Zupancic Judoka, 1990
- Kendall Schmidt Actor, 1990
- Kim Yuna Figure Skater, 1990
- Kimbra Lee Johnson Singer, 1990
- Kiowa Gordon Actor, 1990
- Kirby Bliss Blanton Actress, 1990
- Kirsten Prout Actress, 1990
- Klay Thompson Basketball Player, 1990
- Kris Wu Actor, 1990
- Kristen Stewart Actress, 1990
- Kriti Sanon Actress, 1990
- Krystle D'Souza Actress, 1990
- Lais Ribeiro Model, 1990
- Lala Kent Model, 1990
- Laura Harrier Actress, 1990
- Laura Marling Singer-Songwriter, 1990
- Lauren Potter Actress, 1990
- Lauren Socha Actress, 1990
- Lee Jong-hyun Musician, 1990
- Lee Jun-ho Singer, 1990
- Lee Min-hyuk Singer, 1990
- Lee Seung-hyun Singer-Songwriter, 1990
- Lee Tae-il Singer, 1990