Elon Musk launched Grok 4 and Grok 4 Heavy. These xAI models are meant to challenge the speed, accuracy, and vision of OpenAI’s GPT-5 and Google’s Gemini.

Elon Musk and xAI employee announced on Wednesday night the launch of the startup's next flagship AI model, Grok 4.

This is the smartest AI in the world,” Musk said. He did not mention the chatbot’s viral posts praising Hitler and calling itself “MechaHitler.”