OpenAI's GPT-6 Astra scores 97.6% on Epoch AI's FrontierMath Tier 4 (v2) math benchmark, versus 87.8% for Anthropic's Claude Fable 5.1
OpenAI's GPT-6 Astra model, released on September 3, 2026, scored 97.6% on the FrontierMath Tier 4 (v2) benchmark. This benchmark is part of the Mathematics domain on Epoch AI's platform. Anthropic's Claude Fable 5.1, released on September 1, 2026, scored 87.8% on the same benchmark.
Verified 2026-09-18
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Top models now handle very hard maths, so the gap between leading labs is measured on tougher tests.
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