As of September 2026, OpenAI's GPT-6 Astra, released 3 September 2026, had reached an Epoch Capabilities Index score of 167 — the highest score Epoch AI had recorded among the 251 models it tracked then — two points above Anthropic's Claude Fable 5.1 at 165
The Epoch Capabilities Index (ECI), tracked by Epoch AI, combines AI model benchmark results into one capability score. OpenAI's GPT-6 Astra is a closed-weights model released on September 3, 2026, and it ranked first among tracked models when it was released. Scores and rankings change as Epoch adds models, so the live page now shows slightly different figures.
Verified 2026-10-24
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More on Models
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