Mistral AI Drops 'Le Chonk': A Massive AI Model Named After a Cat Meme

In brief

• Mistral launched Large 4 on Oct. 6, a 1-trillion-parameter model that activates 49 billion parameters per query and costs $1.36 per million input tokens and $4.18 per million output tokens.
• The nickname "Le Chonk" follows the "Le Chaton Fat" meme from June, and Mistral says it will release the model's weights by the end of October.
• On Finance Agent v2, the launch chart shows Large 4 at 54.7, ahead of GPT-6 Astra at 53.5 but behind Claude Opus 5.5 at 58.6.

Paris-based Mistral AI launched Mistral Large 4 on Tuesday, an AI model with 1 trillion parameters. That is the kind of system behind chatbots like ChatGPT and Claude, as parameters are the adjustable numbers it tunes during training—more of them generally means more capacity to learn, and more expensive to run.

“[Mistral Large 4] is at the frontier of open models, and by far the strongest open-weight model from the US or Europe,” Mistral AI’s Chief scientist Guillaume Lample, wrote on X.

Not all of those parameters work at once. Large 4 uses a "mixture of experts" design, meaning the model routes each question to a few specialist sub-networks, so only 49 billion parameters fire per answer. Mistral's last flagship, Large 3, did the same with 41 billion active out of 675 billion.