Paris-based Mistral AI launched Mistral Large 4 on October 6, a 1-trillion-parameter model utilizing a mixture-of-experts architecture that activates 49 billion parameters per query. The company plans to release the model's weights by the end of October, positioning it as a leading open-weight option from Europe or the US. Priced at $1.36 per million input tokens and $4.18 per million output tokens, Large 4 offers significantly lower costs than competitors like Claude Opus 5.5 and GPT-6 Astra.

The launch follows a €3 billion Series D funding round in September led by Samsung, valuing the company above €21 billion. Benchmark results show mixed performance: Large 4 scored 54.7 on Finance Agent v2, surpassing GPT-6 Astra but trailing Claude Opus 5.5. On AutomationBench, it achieved 59.9 points, while DeepSWE 1.1 coding tests yielded a score of 62, placing it behind Kimi K3 but ahead of GLM-5.3 and DeepSeek V4 Pro. The model's nickname, 'Le Chonk,' references a community meme originating from a fictional 'fat kitten' concept popularized in June.