Elon Musk announced that Grok 4.5 has entered private beta testing at SpaceX and Tesla. The model is based on a 1.5T V9 foundation model with added Cursor data.
The update was shared in a post dated June 28. Early evaluations indicate performance close to or possibly exceeding Opus.
Reinforcement learning continues to improve the model, with the Grok Build harness also advancing daily. Musk credited the teams involved for the progress.
New models trained from scratch will be released by SpaceX each month for the remainder of the year.
