Grok 4.5: xAI’s Latest AI Model Enters Private Beta at SpaceX & Tesla
Elon Musk’s artificial intelligence company, xAI, has launched its most potent model to date, Grok 4.5. This model is currently in a private beta deployment across two of Musk’s most engineering-intensive companies: SpaceX and Tesla. Musk announced this rollout on X on June 28, 2026, marking the first real-world deployment of the model before any broader public release.
Grok 4.5 is developed on the xAI’s V9 foundation model. This model boasts a colossal 1.5 trillion parameters, three times larger than the 500 billion-parameter v8-small model currently powering Grok traffic on X. It also represents a 50% scale jump from Grok 4.4, which had approximately 1 trillion parameters and was released just one month earlier in late May 2026. Additionally, the model incorporates supplemental training data from Cursor, the AI-powered coding assistant that SpaceX acquired for $60 billion in June 2026. This acquisition was specifically made to enhance its technical reasoning and coding capabilities.
Musk has stated that early internal evaluations place Grok 4.5’s performance “close to, perhaps exceeding” that of Anthropic’s Claude Opus. However, no independent benchmarks have been published to verify this claim. Analysts have noted that the engineering-heavy workflows of both SpaceX and Tesla provide xAI with a unique real-world testing environment that no other AI lab can replicate. Looking ahead, xAI plans to maintain an aggressive cadence of releasing entirely new foundation models trained from scratch every month through the end of 2026.
Source: The Hans India – Grok 4.5 Enters Private Testing at SpaceX, Tesla