Musk: Grok 4.3 beta is still in the 0.5T training intermediate version, with the 1T flagship only 5 days away from completing the initial training

According to Voyant Beating monitoring, Grok 4.3 (beta) has been opened to users subscribed to the top-tier SuperGrok Heavy. On the 17th, users have seen this version with an "Early Access" tag in the dropdown menu on Grok.com. Early morning on the 18th, user Mark Kretschmann posted that this version features a 1T parameter, twice the size of Grok 4.20, with significantly longer training times. Subsequently, xAI and Tesla CEO Elon Musk clarified in the same thread that the current 4.3 (beta) is still a 0.5T model, just an updated training checkpoint, not the speculated new 1T model.

Musk also revealed that the actual 1T flagship is about 5 days away from completing initial training. He described the 1T model as a significant leap in encoding, long-context, and various skills, stating that the SpaceXAI model factory is up and running, with expectations to release an improved base model every two weeks thereafter.