SpaceXAI CEO Elon Musk announced on Wednesday that Grok 4.5 will be released publicly on Thursday, posting on X, “Based on strong positive feedback from customers in our beta test program, @SpaceXAI will make Grok 4.5 available to the public tomorrow. It is an Opus-class model, but faster, more token-efficient and lower cost.” The public launch comes just under two weeks of internal testing at SpaceX and Tesla. Grok 4.5 runs on xAI’s latest 1.5-trillion-parameter V9 foundation model. The model also reportedly received specialized supplemental training data from Cursor, the AI coding platform that SpaceX is in the midst of acquiring as part of a massive $60 billion deal. Musk also teased that an even larger 2-trillion-parameter V-series model is due for an August release. Musk referenced “Opus-class” based on the current success of competitor Anthropic’s Claude Opus, which is currently on version 4.8. Recent Apptopia data shows that the Grok app’s average daily users in the U.S. dropped by 28% since April, with its market share slipping below 9%.