xAI has launched Grok 4, which it calls “the most intelligent model in the world.” It is live for SuperGrok and Premium+ users and also available through the xAI API. xAI is also adding a new SuperGrok Heavy tier with access to Grok 4 Heavy, its most powerful version. :contentReference[oaicite:0]{index=0}
The headline features are built-in tool use and real-time search. Grok 4 can decide when to open a code tool or browse the web, and it can search across X as well. It can even look at media from X to improve answers. All of this runs natively inside Grok. :contentReference[oaicite:1]{index=1}
xAI says it scaled up reinforcement learning using Colossus, its 200,000-GPU cluster. The team reports a 6× gain in training efficiency and a big expansion of verifiable training data beyond math and code, across many domains. The Grok 4 training run used over an order of magnitude more compute than before. :contentReference[oaicite:2]{index=2}
For tough tasks, the company introduces Grok 4 Heavy. xAI says this model pushes parallel thinking further and “sets a new standard for performance and reliability.” It claims Grok 4 Heavy is the first to score about 50% on “Humanity’s Last Exam,” and that Grok 4 leads on ARC-AGI V2. :contentReference[oaicite:3]{index=3}
Developers get a Grok 4 API with text and vision understanding, a 256,000-token context window, and direct access to live search across X, the open web, and news sources. xAI highlights security and compliance, including SOC 2 Type 2, GDPR, and CCPA. It also says Grok 4 is coming soon to major cloud partners. :contentReference[oaicite:4]{index=4}
There is also a new Voice Mode. xAI says conversations sound more natural, and you can turn on your camera so Grok can “see what you see” and describe the scene in real time.