Moonshot AI just dropped what it calls the largest open-source AI model on the planet. Kimi K3, unveiled at the World Artificial Intelligence Conference in July 2026, carries 2.8 trillion parameters and a context window of 1 million tokens, putting it in a weight class that only a handful of American labs have occupied until now.
Here’s the thing. It’s not just big. It’s cheap. Moonshot is pricing Kimi K3 at roughly $3 per million input tokens and $15 per million output tokens, dramatically undercutting the rates charged by US competitors like OpenAI and Anthropic.
What Kimi K3 actually brings to the table
The model uses a Mixture-of-Experts architecture, a design approach that activates only relevant portions of the model for any given task rather than firing up all 2.8 trillion parameters at once. The result is better efficiency without sacrificing capability.
According to Moonshot’s own benchmarks, Kimi K3 ranks behind only OpenAI’s Claude Fable 5 and GPT-5.6 Sol in overall performance.
