Kimi is the AI made by Moonshot AI, a Beijing lab founded in 2023 by Tsinghua University alumni and backed by Alibaba and Tencent. In just a few years it has grown from a startup into one of the most talked-about names in AI, and its models are among the strongest systems to come out of China. "Kimi" is the consumer brand people chat with; the underlying models are the K-series, and the current flagship is Kimi K3.
Kimi K3 is billed as the largest open-weight model ever built, a multi-trillion-parameter Mixture-of-Experts system with a 1-million-token context window, native vision, and always-on reasoning by default. Because the weights are open, anyone can download and self-host it, which is what makes Kimi genuinely different from the closed models at OpenAI and Anthropic. On Arena's WebDev leaderboard it is the highest-rated open-weight model, ninth overall, with only closed models from US labs above it.
For everyday work, that translates into a model that can hold an entire codebase or a stack of documents in its head at once, chain tools together to complete multi-step tasks, and read images alongside text. If you need an AI for long-context analysis, agentic automation, or hands-on coding, Kimi K3 is a genuine frontier-level option, and it is free to try.
Kimi vs Kimi K3: Kimi is the app and brand from Moonshot AI. K3 is the current flagship model in its K-series, alongside specialized variants for agentic and reasoning work. In Fello AI, Kimi queries are routed through secure US-based servers, not through Moonshot's own infrastructure.