Kimi K2

Kimi K2 is a large language model built by Moonshot AI, released as an open-weight mixture-of-experts model with 1 trillion total parameters and 32 billion activated per token. It was trained with the Muon optimizer and tuned specifically for agentic work: tool use, coding, and multi-step reasoning rather than general chat alone, with a context window that Moonshot has extended in later K2 versions to handle long documents and codebases. The model weights are open and available for self-hosting, and Moonshot also offers an OpenAI- and Anthropic-compatible API through platform.moonshot.ai for developers who don't want to run it themselves. The consumer-facing kimi.com product built on the Kimi models adds a chat interface, a coding assistant called Kimi Code, a work-focused mode, plugins, and the ability to hand off scheduled or multi-step tasks to an agent. At 1 trillion total parameters, self-hosting the full model requires substantial GPU infrastructure, which is why most developers use it through the hosted API or inference providers instead of running it locally.