SpaceXAI has launched Grok 4.5, its first model created after rebranding from xAI and developed with assistance from AI company Cursor. Grok 4.5 is now the default model for SpaceXAI’s terminal-based AI coding agent, Grok Build.
The model was trained on tens of thousands of NVIDIA GB300 GPUs using datasets that encompass coding, science, engineering, and math information. SpaceXAI claims Grok 4.5 outperforms other leading models at real engineering tasks and excels in creating functional applications with minimal instructions.
For example, Grok 4.5 was able to generate an interactive solar system simulation from a single prompt. The model is designed to respond faster than “flash” models while providing results at significantly lower costs, priced at $2 per million input tokens and $6 per million output tokens.
In comparison, OpenAI’s GPT-5.6 most powerful variant, Sol, costs $5 per million input tokens and $30 per million output tokens, while its more affordable Luna variant is priced at $1 per million input tokens and $6 per million output tokens.
Grok 4.5 can also be used for tasks beyond coding, including functions in Excel, PowerPoint, and Word. It is accessible through the SpaceXAI console and integrated into all of Cursor’s plans.
In April, SpaceXAI and Cursor formed a partnership to jointly develop AI technologies. The partnership may involve SpaceXAI investing $10 billion into Cursor or pursuing an acquisition for $60 billion later in the year; however, a final decision has not been disclosed.
Currently, Grok 4.5 is not available to users in the European Union, with its rollout expected in mid-July.
