No longer served by Moonshot's API, so this is now only for developers willing to host a trillion-parameter model themselves.

Kenning's take

What it does

Kimi K2 is a mixture-of-experts language model from Moonshot AI with 1 trillion total parameters, 32 billion of them active per token, and a 128K context window. It came as a Base model for fine-tuning and an Instruct model for chat and agent tasks. Moonshot's API stopped serving the K2 series on 25 May 2026, so it is now used through the open weights on Hugging Face.

• 1 trillion total parameters, 32 billion active
• 128K token context
• Base and Instruct versions
• Trained on 15.5 trillion tokens with the MuonClip optimiser
• Modified MIT licence for code and weights

Who it suits. Developers and researchers who want to run or fine-tune a large open model for coding and agent work.

Key facts

Category

AI models

Part of

Kimi

Made by

Moonshot AI

Based in

China

Released

11 July 2025

How to get it

open weights on Hugging Face under a Modified MIT licence; Moonshot's own API discontinued the K2 series on 25 May 2026

Works on

self-hosted, Hugging Face

Free plan

Weights free to download under the Modified MIT licence

FAQ

Facts from the maker's own pages and the sources listed. Checked 2026-10-11.