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Pyyan / Compare / Gemini 3.8 Flash vs Claude Fable 5.1

Gemini 3.8 Flash vs Claude Fable 5.1

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Language Models · verified 5 Sept 2026

Gemini 3.8 FlashGooglecurrent
Claude Fable 5.1Anthropiccurrent
3 slots left
SpecificationGemini 3.8 FlashClaude Fable 5.1
Summary$0.75 per million in, until the introductory rate ends on 1 January.Same price as Fable 5, and cache reads cost a quarter of what they did.
Context1M1M
Input ($/Mtok)$0.75$10
Output ($/Mtok)$3.75$50
LicenceProprietaryProprietary
Max output64K128K
ParametersNot publishedNot published
Released2 Sep 20261 Sep 2026
Model IDgemini-3.8-flashclaude-fable-5-1
CategoryLanguage ModelsLanguage Models
Official——

Highlighted rows are where these differ.

Gemini 3.8 Flash

  • Introductory pricing runs to 31 December 2026, then input and output both double
  • A separate Flash Cyber twin clears 70% on real world vulnerability discovery
  • Flash Cyber is reachable only through the Fairwind Program, by application

Best for high volume work at low cost.

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 →