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GPT-6 Astra characterClaude Sonnet 5.5 characterClaude Opus 5.5 character

Claude Opus 5.5, Sonnet 5.5 and GPT-6 Astra

3 models from Anthropic and OpenAI

Benchmark

Epoch: Opus 5.5 takes the top spot on the Epoch Capabilities Index

Epoch AI reported Opus 5.5 first on its Epoch Capabilities Index with 167, narrowly ahead of GPT-6 Astra, and Sonnet 5.5 roughly matching Fable 5.1 (165). Epoch's current ECI data lists Opus 5.5 at 168.83, GPT-6 Astra 168.81, GPT-6.1 Sol 168.37, Gemini 4 Argon 166.45, Sonnet 5.5 166.18 and Opus 5 163.94.

Source

"Claude Opus 5.5 took the top spot on the Epoch Capabilities Index with a score of 167, narrowly ahead of GPT-6 Astra."

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Published

Open the sourceepoch.ai

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