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Pyyan / Compare / Grok 4.6 vs Claude Fable 5.1

Grok 4.6 vs Claude Fable 5.1

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Language Models · verified 2 Sept 2026

Grok 4.6xAIcurrent
Claude Fable 5.1Anthropiccurrent
3 slots left
SpecificationGrok 4.6Claude Fable 5.1
SummaryNewest xAI flagship.Same price as Fable 5, and cache reads cost a quarter of what they did.
Context500K1M
Input ($/Mtok)$2$10
Output ($/Mtok)$6$50
LicenceProprietaryProprietary
Max output—128K
Parameters—Not published
Released12 Aug 20261 Sep 2026
Model IDgrok-4.6claude-fable-5-1
CategoryLanguage ModelsLanguage Models
OfficialxAI ↗—

Highlighted rows are where these differ.

Grok 4.6

  • Tiered pricing: doubles above 200K tokens
  • Smaller context than Grok 4.3 despite being newer

Best for cost-sensitive scale.

Full spec sheet →

Claude Fable 5.1

  • Matches or beats Fable 5 at low and medium effort, and pulls clear at high effort
  • Cache reads cut to 25% of the old price, so re-reading a long context got much cheaper
  • Identical model to Mythos 5.1 underneath; the difference is the safeguards

Best for coding and long-running work.

Full spec sheet →