SAN FRANCISCO — SpaceXAI has released Grok 4.5, the first artificial-intelligence model it built hand-in-hand with coding startup Cursor, and the launch reads like a preview of a much larger union. The companies now describe Grok 4.5 as the default engine behind Cursor's tools and SpaceXAI's own terminal agent, Grok Build, tightening an alliance that could culminate in a $60 billion acquisition later this year.
The rollout, confirmed on July 8, is the first flagship model shipped since Musk folded xAI into SpaceX and rebranded the group as SpaceXAI. It signals that the combined company intends to compete directly with Anthropic and OpenAI on the terrain that matters most to enterprise buyers: software engineering, agentic work, and everyday office tasks.
A Model Built For Work
SpaceXAI trained Grok 4.5 across tens of thousands of NVIDIA GB300 GPUs on datasets heavy in coding, science, and mathematics, and pitched it as its 'smartest model yet.' The company says it beats rival systems at real engineering tasks and can spin up functional apps from minimal prompts — in one demo, generating an interactive solar-system simulation from a single instruction.
Crucially, Grok 4.5 is priced to undercut. At $2 per million input tokens and $6 per million output tokens, it lands well below the most powerful tiers from competitors, a pricing posture that mirrors the cost discipline Musk emphasized when he called Grok 4.5 an 'Opus-class' model. Speed is part of the pitch too: SpaceXAI says the model responds faster than rival 'flash' variants while delivering higher-quality output.
