Musk’s xAI unveils Grok 4 with a $300 subscription for the premium version

Elon Musk unveiled xAI’s latest AI model, Grok 4, rivaling ChatGPT and Gemini, during a livestream on X. Claiming it as the “smartest AI in the world,” Musk also announced a new $300 monthly subscription plan called SuperGrok Heavy. 

xAI has stated that Grok 4 surpassed competitors scoring 25.4% on Humanity’s Last Exam without “tools” beating out Gemini 2.5 Pro (21.6%) and OpenAI’s o3 which scored 21%. The benchmark comprises more than 2,500 questions on dozens of subjects including maths, science and linguistics. 

The AI model will also be able to analyse images and respond to questions. 

Meanwhile, Grok 4 Heavy is their multi-agent variant that shows better performance. The company claimed that the model’s multiple agents work together on problem and then compare their results to determine the best outcome. 

Grok 4 Heavy scored 44.4% on the Humanity’s Last Exam benchmark, outperforming Gemini 2.5 Pro’s 26.9%. 

“Grok 4 is the first time, in my experience, that an AI has been able to solve difficult, real-world engineering questions where the answers cannot be found anywhere on the Internet or in books. And it will get much better,” Musk posted on X. 

The release comes during a rocky time for both X and xAI. Just yesterday, X CEO Linda Yaccarino resigned from her position after a two-year tenure. 

Earlier this week, Grok started spewing antimsemitic comments on X a day after Musk expressed that the chatbot was becoming too “biased” and politically correct. The posts were later removed after a furore.