- Aug 2 Mark Lee, Canadian rapper and singer (NCT; SuperM), born in Toronto, Ontario
- Aug 3 Brahim Díaz, Spanish footballer (Real Madrid), born in Málaga, Spain
- Aug 3 Zach Wilson, American NFL quarterback (NY Jets), born in Draper, Utah
- Aug 7 Sydney McLaughlin, American hurdler and sprinter, born in New Brunswick, New Jersey
- Aug 10 Ja Morant, American NBA player (Memphis Grizzlies), born in Dalzell, South Carolina
- Aug 12 Matthijs de Ligt, Dutch football player (Bayern Munich, Netherlands), born in Leiderdorp, Netherlands
- Aug 19 Ethan Cutkosky, American actor (Shameless), born in St. Charles, Illinois
- Aug 28 Prince Nikolai of Denmark, born in Copenhagen, Denmark
- Aug 31 Shamar Joseph, West Indian cricket fast bowler (Test BB 7/68 v Australia 2024; Guyana), born in Baracara, Guyana
About August 1999
How Old? 24 or 25 years old
Generation: Generation Z
Leap Year: No
Greatest Generation
Silent Generation
Baby Boomer
Generation X
Millennial
Generation Z