Scoop: Musk's SpaceXAI releases new model, Grok 4.5
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Elon Musk's SpaceXAI is launching Grok 4.5, its smartest model yet, and its first release since going public and acquiring the AI coding startup Cursor.
Why it matters: The new model is being pitched as a coding and agentic-work tool, more than a consumer-facing chatbot — one that Musk says is "maximally truth-seeking" compared to its competitors.
Zoom in: The company says Grok 4.5, trained alongside Cursor, outperforms comparable models on engineering and knowledge work.
- "It is an Opus-class model, but faster, more token-efficient and lower cost," wrote Musk in a post on X, referencing what was until recently Anthropic's top model family.
- A chart accompanying the announcement says the model outperforms Opus 4.8 on several key benchmarks.
- Grok 4.5 is available today in Grok Build, in Cursor on all plans, and from the SpaceXAI console, though Grok 4.5 is not yet available in the EU.
Between the lines: SpaceXAI claims the new Grok outperforms some OpenAI and Anthropic models on speed, price and performance, but not the largest, latest models from those competitors.
- Musk expects to beat and exceed those models soon.
By the numbers: Grok 4.5 is a bargain for users, the company argues, priced at $2 per million input tokens and $6 per million output tokens.
- Claude's Opus 4.8, by comparison, is priced at $5 per million input tokens and $25 per million output tokens. OpenAI's GPT 5.6 Luna is priced at $1 input / $6 output.
The intrigue: This model was trained using the same compute capacity SpaceXAI is leasing to its competitors Anthropic and Google.
- As its own compute needs grow, SpaceXAI may have to choose between using capacity for its own models or leasing it to others as a revenue stream.
Zoom in: It's a big day for model releases.
- OpenAI said it will release GPT 5.6 widely on Thursday, following the Trump administration's request for limited release.
- OpenAI is also releasing a new generation of voice models.
The bottom line: SpaceXAI is positioning Grok as a serious contender for business use that can be cheaper than rivals, even if it currently trails the performance of its competitors' best models.
