Elon Musk posted on July 17, 2026, that Grok 4.5 is “arguably #1” among AI models once speed and cost are factored in alongside raw capability. The claim positions xAI’s latest model not just as a performance competitor but as an efficiency play — a framing that matters to developers and enterprises weighing inference costs at scale.
The post arrived amid an intensifying race between xAI, OpenAI, and Anthropic, where each new model release is quickly benchmarked against the others. By emphasizing the speed-and-cost dimension rather than benchmark scores alone, Musk is carving out a distinct value proposition for Grok 4.5 in a crowded field.
The tweet drew over 1,500 likes, 529 replies, and 212 retweets, suggesting the claim landed with meaningful engagement from the AI and investor communities. Musk linked out to supporting material, though the underlying benchmarks or third-party data behind the “arguably #1” label were not detailed in the post itself.