OpenAI has detailed the extensive five-month process used to select the five distinct voices for ChatGPT: Breeze, Cove, Ember, Juniper, and Sky. Beginning in early 2023, the company partnered with award-winning casting directors to establish specific criteria, prioritizing timeless, approachable, and trustworthy voices. This initiative resulted in over 400 submissions from voice and screen actors, which were narrowed down to 14 finalists before the final five were chosen.

The selection process emphasized ethical collaboration with the creative community, ensuring actors received compensation above market rates. A notable controversy arose regarding the voice 'Sky,' with concerns it resembled Scarlett Johansson. OpenAI CEO Sam Altman clarified that Sky's voice belongs to a different professional actress and was cast prior to any outreach to Johansson.

Out of respect, OpenAI has paused the use of Sky's voice. This transparency highlights the complexities of AI voice development and the importance of protecting creative talent.