Kimi K3 is a 2.8-trillion-parameter multimodal Mixture-of-Experts model developed by Moonshot AI. It is designed for long-horizon coding, reasoning, knowledge work and agent tasks. It supports text, image and video input and has a 1-million-token context window.

How much does Kimi K3 cost?

The Kimi K3 API costs $3 per million uncached input tokens, $0.30 per million cached input tokens and $15 per million output tokens. Moonshot applies the same rates across the full 1-million-token context window.

What is the Kimi K3 context window?

Kimi K3 has a 1-million-token context window. The API’s maximum completion setting defaults to 131,072 tokens and can be raised to 1,048,576 tokens.

Is Kimi K3 open source?

Moonshot describes Kimi K3 as an open-source model, but its full weights weren’t available as of July 24, 2026. The company says it will release them by July 27. Developers should review the final license before assuming unrestricted commercial use, modification or redistribution.

How does Kimi K3 compare with GPT-5.6 and Claude?

Kimi K3 leads several of Moonshot’s reported agent and productivity benchmarks, including BrowseComp, SpreadsheetBench 2 and Automation Bench. GPT-5.6 Sol remains ahead on some terminal and coding tests, while Claude Fable 5 leads FrontierSWE and several difficult reasoning evaluations. Kimi K3’s main advantage is that it approaches their performance at a lower API price.