Overview
Kimi K3.1 Pro is an open-weight, natively multimodal agentic model and the first model in the K3.1 series. It is post-trained from Kimi K3. Its mixture-of-experts architecture has 2.8 trillion total parameters, 104 billion activated parameters, and a 1,048,576-token context window. The official model card lists text and image modalities. (huggingface.co)
Capabilities and uses
The model is intended for complex coding, tool-assisted workflows, visual understanding, 3D creation, financial research, and long-context analysis. Moonshot describes using it to generate scripts for tools such as Blender and CAD software; those workflows depend on the relevant external tools and integrations. The API supports configurable reasoning effort and tool calls. (kimi.com)
Availability and limitations
The weights are available under the Kimi K3.1 Pro License; users should review its terms before deployment. For multi-turn API conversations and tool calls, the official model card says to preserve the complete assistant message, including reasoning content and tool calls. Outputs can be incorrect and should be independently checked, especially for financial or other consequential uses. (huggingface.co)
Release date
The supplied record gives November 5, 2026. The supplied X announcement returned HTTP 403 when accessed, so its content and date could not be independently verified. Moonshot's Chinese launch announcement is marked updated October 24, 2026 and says the model was available from that announcement. The November 5 date should therefore not be treated as a verified initial launch date. (kimi.com)
Official API pricing
Prices below are for the standard K3.1 Pro, not the separately priced Highspeed version. One MTok means one million tokens. The domestic and international platforms are separate offerings; their prices are not currency conversions.
- Mainland China platform, CNY: input ¥13.00/MTok; output ¥68.00/MTok; cache write ¥13.00/MTok; cache hit ¥1.30/MTok. Official domestic pricing — checked November 15, 2026. (platform.kimi.com)
- International platform, USD: input $2.00/MTok; output $10.00/MTok; cache write $2.00/MTok; cache hit $0.20/MTok. Official international pricing — checked November 15, 2026. (platform.kimi.ai)