Moonshot AI releases open weights for Kimi K3.1 Pro

Moonshot AI has published the weights for Kimi K3.1 Pro, an open-weight model that handles both text and images and the first release in its K3.1 series. It is a mixture-of-experts design with 2.8 trillion total parameters and 104 billion active per token, and it accepts context windows of roughly one million tokens. The company says it post-trained the model from Kimi K3 using large-scale joint reinforcement learning across hundreds of task domains, and it reports improvements in coding, 3D creation, financial research, factual accuracy and other agentic work. Weights are downloadable on Hugging Face in 8-bit precision, and an API is also offered. The model card includes benchmark comparisons against other open and proprietary models.