Kimi K3

Kimi K3 is Moonshot AI's open-weight model, built for long-horizon reasoning and coding work that runs across many steps instead of a single response. It's a mixture-of-experts model with 2.8 trillion total parameters and 104 billion active parameters, with roughly 1 million tokens of context per Moonshot's own model card. It handles multi-file codebases, agentic tool-calling loops, and extended chains of reasoning at a scale that puts it in range of the top closed frontier models on independent coding and math benchmarks.

Access is available through the API at usage-based rates, and the full model weights are now released under the Kimi K3 License with deployment guidance on Moonshot's Hugging Face repository, so teams can self-host today rather than depend on a single vendor's uptime and pricing. Downloading the weights themselves carries no charge, but running a model this size takes serious infrastructure, so most users will start on the hosted API and only move to self-hosting once they have the hardware to justify the nonzero compute cost. Kimi K3 fits engineering teams and researchers who want frontier-level reasoning and coding performance with the option to run the model on their own infrastructure instead of staying locked into a single API.