Musk Announces Grok 4.5 with 1.5T Parameters and Enhanced Coding

On July 8, Elon Musk announced that xAI would release the Grok 4.5 model to the public the following day, based on strongly positive feedback from beta testers. He claimed the model achieves Opus-level performance but is faster, more token-efficient, and cheaper. This official news corroborated a wave of recent online leaks.

Key Details and Rumor Roundup

Prior to official confirmation, several leakers and test accounts revealed extensive details. According to information compiled by @tetsuoai and @XFreeze, Grok 4.5 runs on a new V9 base model with 1.5 trillion parameters, three times the size of the previous V8-small (0.5T), making it xAI's largest model to date. The training focused heavily on coding and agentic tasks. Additionally, @nimaowji and @testingcatalog spotted traces of version 4.5 on the Grok web frontend, and @markk leaked that early access would be restricted to SuperGrok Heavy subscribers.

Deep Collaboration with Cursor

Multiple sources indicated a deep collaboration between xAI and the coding tool Cursor. According to internal memos and media reports relayed by @kimmonismus and @ns123abc, the two parties co-developed the model to directly compete with Opus 4.8 and GPT 5.5 in key areas. @haider1 added that the model was trained on Cursor data to boost agentic programming capabilities. However, @Angaisb noted that while they hold low expectations for xAI itself, they trust Cursor's ability to optimize it.

Future Model Roadmap

Alongside the Grok 4.5 announcement, Musk (@elonmusk) shared future development plans. He stated that the Grok Build harness and the 1.5T base model would see continuous daily improvements based on user needs, while the larger Grok 2T model will finish training this month and be made available to customers next month.

2026-07-07 ~ 2026-07-09 · 25 related posts

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1 near-duplicate retellings: JOBhakdi