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SwapClaude Opus 5.5
Anthropic's new Claude Opus 5.5 writes text and answers questions, offered to developers and paying users, not free to download.
Release page →Gemini 4 Argon
Google's next Flagship: A lab's best and usually most expensive model, the one it leads with. AI model for writing, answering questions and Reasoning model: A model that thinks step by step before answering. Slower, but much better at maths, code and tricky questions., currently open only to limited testers rather than the public.
Release page →The basics
Released
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The latest events it learned about
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Combined test score
Epoch Capabilities Index · Epoch AI
Too close to call: Claude Opus 5.5 and Gemini 4 Argon are within the margin of error.
Chat answers, by people's votes
LMArena text, adjusted for style · LMArena
Neck and neck: in blind votes, people pick each about as often as the other.
Building apps, by people's votes
LMArena WebDev · LMArena
In blind votes, people pick Claude Opus 5.5 over Gemini 4 Argon about 69% 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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