Elon Musk unveils Grok 4.5 as OpenAI readies GPT-5.6 showdown

Elon Musk has confirmed that SpaceXAI will release its Grok 4.5 artificial intelligence model to the public on Thursday after completing beta testing, setting up a direct contest with OpenAI’s upcoming GPT-5.6 launch.

According to Elon Musk, the decision follows strong feedback from users who tested Grok 4.5 during its beta phase. In a post on X, Musk described the model as “an Opus-class model, but faster, more token-efficient, and lower cost,” adding that the public rollout will begin tomorrow. 

The announcement places Grok 4.5 alongside several major AI releases expected this week as competition between leading developers continues to accelerate.

At nearly the same time, OpenAI confirmed that its GPT-5.6 family, consisting of the Sol, Terra, and Luna models, will also become publicly available on Thursday. The announcement follows approval from the U.S. Commerce Department for a broad public launch, as previously reported by crypto.news. OpenAI’s choice of model names attracted attention within the crypto industry because they match names of some of the crypto industry’s best-known blockchain projects.

Last month, Anthropic added to the competitive landscape by releasing its Fable 5 and Mythos 5 models, which the company described as its most capable AI systems to date. Those models were temporarily restricted under U.S. export controls before the government later removed the limitations, allowing wider availability.

Grok 4.5 introduces a larger foundation model

Additional technical details shared by developer Tetsuo indicate that Grok 4.5 is built on xAI’s V9 foundation model, which contains roughly 1.5 trillion parameters. According to Tetsuo, the architecture is around three times larger than the v8-small model that powered Grok 4.3, making it the largest foundation model the company has released so far.

Tetsuo added that the model was trained on Nvidia Blackwell GPUs at the Colossus computing cluster in Memphis. He also stated that software development capabilities have become a central priority for Grok 4.5 after SpaceXAI incorporated developer data from Cursor into supplemental training. According to the developer, reinforcement learning has continued improving the model through the Grok Build training framework.

crypto.news previously reported that SpaceXAI completed its acquisition of Cursor, a move that expands the company’s access to software engineering datasets. Tetsuo noted that the next foundation model, which is already undergoing training, will include Cursor data from the beginning of the pre-training process rather than adding it later.

Monthly flagship releases form the long-term roadmap

Beyond the immediate launch, Tetsuo outlined a more aggressive release schedule for future models. He described Grok 4.5 as the first flagship model introduced under the merged SpaceXAI organization and said the company plans to ship a newly built foundation model every month through the end of 2026.

While Musk focused on Grok 4.5’s performance, speed, and operating cost, Tetsuo’s technical comments suggest that future versions will continue expanding coding capabilities through larger training datasets and updated reinforcement learning methods.

With Grok 4.5, OpenAI’s GPT-5.6 lineup, and Anthropic’s recently released models entering the market within weeks of one another, competition among leading AI developers is intensifying as each company pushes newer foundation models to public users and enterprise customers.