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SwapStep 5 Preview
StepFun's Step 5 Preview: An early version released for testing. It may change or disappear, and is often limited while it lasts. is a very large text model for writing and answering questions, offered to developers and not free to download.
Release page →Kimi K3
Moonshot AI's Kimi K3 is a very large model that can read text, images and video, free to download for research and non-commercial use and aimed at long coding and knowledge-work tasks.
Release page →The basics
Released
What it does
Knowledge cutoff
The latest events it learned about
Download
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How they score
Combined test score
Epoch Capabilities Index · Epoch AI
Only Kimi K3 is in this ranking.
Chat answers, by people's votes
LMArena text, adjusted for style · LMArena
In blind votes, people pick Kimi K3 over Step 5 Preview about 56% of the time.
Building apps, by people's votes
LMArena WebDev · LMArena
In blind votes, people pick Kimi K3 over Step 5 Preview about 62% of the time.
Green marks the better of the two on each row, red the other. Rows where one side isn't listed, or where the gap is too close to call, stay plain.
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Rankings from LMArena and Epoch AI, both CC BY 4.0, updated . Developer prices, context windows and knowledge cutoffs from the labs' own listings on models.dev and from OpenRouter. The app links go to each maker's own app when no source says exactly where the model is available.