SpaceXAI — formerly xAI — has officially launched Grok 4.5, the first large language model developed in collaboration with AI coding startup Cursor. The new model marks a significant milestone in the Elon Musk-led company’s rebound from its parent organization and establishes a deeper technical partnership between the two AI firms.
A Model Built for Engineering
Grok 4.5 was trained across tens of thousands of NVIDIA GB300 GPUs on datasets heavily weighted toward coding, science, engineering, and mathematics. SpaceXAI claims it is its “smartest model yet,” purpose-built to excel at coding, agentic tasks, and knowledge work.
According to the company, Grok 4.5 outperforms leading competitors at real-world engineering challenges. It can generate fully functional applications from minimal instructions — in one demonstration, the model produced an interactive solar system simulation from a single natural-language prompt.
Pricing and Performance
SpaceXAI positions Grok 4.5 as a high-performance, cost-efficient alternative to rival models. The company says it responds faster than traditional “flash” models while delivering results at significantly lower costs.
The pricing structure is as follows:
- Input tokens: $2 per million tokens
- Output tokens: $6 per million tokens
For comparison, OpenAI’s GPT-5.6 family offers its most powerful variant, Sol, at $5 per million input tokens and $30 per million output tokens. Its more affordable Luna variant comes in at $1 per million input and $6 per million output — placing Grok 4.5 competitively in the mid-range segment.
Where to Find Grok 4.5
Grok 4.5 is now the default model powering Grok Build, SpaceXAI’s terminal-based AI coding agent. Beyond software development, Grok Build also supports productivity tasks in Excel, PowerPoint, and Word, broadening its appeal beyond engineers.
The model is accessible via the SpaceXAI console and is included across all of Cursor’s plans. Cursor announced the partnership on X, stating: “We’ve partnered with SpaceXAI to train Grok 4.5. It’s our most powerful model yet and the first we’ve built for more than software engineering.”
The SpaceXAI-Cursor Partnership
The launch follows the landmark partnership announced in April 2026 between SpaceXAI and Cursor. The deal includes two potential outcomes: SpaceXAI either investing $10 billion into Cursor, or acquiring the company outright for a reported $60 billion later this year. A final decision has not yet been announced.
Availability
Grok 4.5 is available now for users outside the European Union. SpaceXAI expects to bring the model to EU markets by mid-July 2026, pending regulatory compliance.
With competitive pricing, strong engineering performance, and deep Cursor integration, Grok 4.5 positions SpaceXAI as a serious contender in the rapidly evolving AI landscape — especially for developers and enterprises seeking powerful agentic coding assistance.