SpaceXAI launches Grok 4.5, its first built with Cursor’s help
By Mariella Moon — July 9, 2026 7:48 am EST
SpaceXAI has launched the first Grok model after its rebranding from xAI and the first one it trained with AI company Cursor. The company says Grok 4.5 is its smartest model yet, built specifically “to excel at coding, agentic tasks and knowledge work.” It was trained across tens of thousands of NVIDIA GB300 GPUs on datasets full of coding, science, engineering and math information.
The model, SpaceXAI claims, outdoes other leading models at real engineering tasks and is highly proficient at creating functional apps with minimal instructions. In one example, Grok 4.5 generated an interactive simulation of the solar system with a single prompt. SpaceXAI also says that it was designed to respond faster than “flash” models and to deliver results “at far lower costs.”
Pricing
Grok 4.5 is priced at 6 per million output tokens. For comparison, OpenAI GPT-5.6’s most powerful variant, Sol, costs 30 per million output. GPT-5.6’s most affordable variant, Luna, costs 6 per million output.
Availability
Grok 4.5 is now the default model powering the company’s terminal-based AI coding agent Grok Build, which you can use not just for coding, but also for Excel, PowerPoint and Word tasks. It’s also available from the SpaceXAI console and in all of Cursor’s plans.
“We’ve partnered with SpaceXAI to train Grok 4.5,” Cursor announced on X. “It’s our most powerful model yet and the first we’ve built for more than software engineering.”
Cursor partnership
In April, SpaceXAI and Cursor struck a partnership to develop AI together. The deal could see SpaceXAI either investing 60 billion. They have yet to reveal their decision.
Grok 4.5 is not yet available in the European Union, where it’s expected to become available in mid-July. It had been in private beta at SpaceX and Tesla since late June before this public release.