Moonshot AI publishes the weights of its 2.8-trillion-parameter Kimi K3.1 Pro model

Moonshot AI, the Beijing company led by co-founder and chief executive Yang Zhilin, released the model weights for Kimi K3.1 Pro on Hugging Face on November 4. Kimi K3.1 Pro is the company's most capable model and has 2.8 trillion parameters. The release fulfills a promise Moonshot made when it introduced the model in October. The company announced it in a post on X that linked to the repository and said: "We'll keep advancing open intelligence." The weights come under a Kimi-specific license rather than a standard open-source license, so some limits on use remain. With the weights available, developers can download and run the model themselves instead of relying only on Moonshot's API. Outside teams can also test the company's coding and agent claims with their own evaluation setups. Customers now have a self-hosting option to weigh against hosted pricing. However, a model of this size needs substantial hardware to serve. The release adds to a series of very large open-weight models from Chinese labs, and it gives researchers and companies another frontier-scale option they can inspect and deploy themselves.