Grok 4: xAI launches its new model and the Grok 4 Heavy variant
In one sentence On July 9, 2025 xAI unveils Grok 4 and Grok 4 Heavy, which uses parallel test-time compute, in a livestream. New SuperGrok Heavy plan at $300/month, API with a 256K-token context. The launch comes the day after Grok's antisemitic posts on X.
xAI, Elon Musk's company, presents Grok 4 in a livestream on July 9, 2025. Alongside the base model comes Grok 4 Heavy, a version that weighs several hypotheses in parallel before answering, using more compute.
Grok 4 is available to SuperGrok and X Premium+ subscribers and to developers via the API. For Grok 4 Heavy there is a new subscription, SuperGrok Heavy, at 300 dollars per month.
xAI claims top results on hard tests such as Humanity's Last Exam and ARC-AGI-2; these are company-reported numbers. The launch comes the day after Grok, on the X social network, posted antisemitic messages (even calling itself "MechaHitler"), which xAI then deleted.
Companies
xAI
Tools
Grok 4, Grok 4 Heavy
Tags
Sources