Mistral AI releases open weights for 1T-parameter Mistral Large 4

Released on 29 October 2026 under the Mistral Ecosystem Open-Weight licence, Mistral Large 4 permits unrestricted self-hosting, fine-tuning, and internal enterprise deployment, while commercial Model-as-a-Service redistribution requires a separate licence from Mistral AI. Trained in Europe, the updated weights incorporate additional reinforcement learning post-training for multi-repository software engineering and defensive cybersecurity workflows, and expose three selectable reasoning effort modes: Low, Medium, and High (the default).

As illustrated in the Hugging Face release architecture diagram, the model pairs a native Pixtral vision encoder with 72 sparse Mixture-of-Experts decoder layers supporting roughly a 1 million token context window. Mistral AI renders its benchmark comparisons interactively in HTML on the announcement page rather than as static chart images, reporting first place among open models on Cognition’s FrontierCode 2.0, a tie with GLM-5.3 on the Artificial Analysis Coding Agent Index using nearly half as many tokens, and 30% lower output token usage on Terminal-Bench 4.0 than its preview checkpoint.

Key numbers

• 19.7% on Cognition FrontierCode 2.0, ranking first among open-weight models.
• 48% on the Artificial Analysis Coding Agent Index while consuming 47% fewer tokens than GLM-5.3.
• 41% on Terminal-Bench 4.0, a 13 percentage point gain over the Mistral Large 4 preview checkpoint.