Mistral releases open weights for Mistral Large 4, its 1-trillion-parameter model
Mistral released the weights of an improved Mistral Large 4 (nicknamed Le Chonk), a 1-trillion-parameter multimodal model it positions for agentic coding and defensive cybersecurity, under a modified MIT license that requires a separate commercial license only for model-as-a-service providers.
What happened
- On October 29, 2026, Mistral published the weights of Mistral Large 4, three weeks after a public preview, saying further reinforcement learning improved coding, cybersecurity and reasoning efficiency.
- The weights are on Hugging Face for self-hosting with vLLM or SGLang; the model is also available in Mistral Studio, the Mistral API, OpenRouter, Microsoft Foundry and NVIDIA-hosted endpoints.
- Mistral reports 48% on the Artificial Analysis Coding Agent Index, about level with GLM-5.3 while using 47% fewer tokens per task, and 41% on Terminal-Bench 4.0; it adds Low, Medium and High (default) reasoning modes.
- Mistral reports 51% on the Artificial Analysis Cyber Index and a 96.6% average refusal rate on malicious cyber prompts, but says it saw potential uplift for real attacks and is updating its guardrails.
- API pricing starts at $0.70 per million input tokens, $0.07 cached input and $2.10 per million output tokens, per Mistral.
Why it matters: It gives businesses a large, commercially usable model they can run on their own servers for coding and security work, at API prices well below most closed frontier models. Mistral's own caution about misuse is also a reminder that open weights can't be recalled once downloaded.
Sources
- Mistral: Mistral Large 4 (Le Chonk) is now open weight mistral.ai
- Hugging Face: Welcome Le Chonk, Mistral Large 4 on Hugging Face huggingface.co
Checked October 30, 2026 against the sources above. Claims about performance or benchmarks are the company's own unless stated otherwise.