Elon Musk on Saturday announced that xAI's newest model, Grok 4.5, has entered private beta testing in SpaceX and Tesla, and that early internal evaluations show the model performing close to, and in some cases surpassing, Anthropic's Opus model.
"Grok 4.5, based on our 1.5T V9 foundation model, with Cursor data added in supplemental training, is now in private beta at SpaceX & Tesla. Early evals show performance close to, perhaps exceeding Opus," he wrote on X.