- 1 Odessa
- 2 Olivia Herdt
- 3 Olivia Addams
- 4 Otilia
- 5 One-T
- 6 Orianthi
- 7 Oceanside
- 8 Oh Susanna
- 9 Orkid
- 10 Oh Land
- 11 Olivia Belli
- 12 Olivia Dean
- 13 OR3O
- 14 Olga Lounova
- 15 Olivera
- 16 Ony
- 17 Origa
- 18 Oceana
- 19 Otis McDonald
- 20 OSTON
- 21 ooxygen
- 22 Odetta
- 23 Ornella Vanoni
- 24 Okay Kaya
- 25 Olivia Broadfield
- 26 Olivia Ruiz
- 27 Ofelia
- 28 Olivia Newton-John
- 29 Olivia O'Brien
- 30 Ofelia Del Rosal