Grok 4

Grok 4 is xAI's flagship multimodal reasoning model released on 9 July 2025, alongside the Grok 4 Heavy variant available to SuperGrok Heavy subscribers. xAI claims Grok 4 outperforms rival models on benchmark tests (xAI does not publicly disclose specific numbers outside its promotional materials). The model features native tool use and built-in real-time search (Web Search and X Search). Knowledge cutoff: November 2024 (confirmed in docs.x.ai). Context window: 256K tokens. From 12 July 2025 it has been deployed in Tesla Model S, 3, X, Y, and Cybertruck via the 2025.26 software update. The same month xAI announced "Grok for Government" — a contract worth up to $200M with the U.S. Department of Defense (alongside Anthropic, Google, and OpenAI). Since 10 August 2025, free users have had limited access (2 prompts every 2 hours).