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Pyyan / Compare / Claude Opus 5 vs Claude Fable 5

Claude Opus 5 vs Claude Fable 5

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Language Models · verified 13 Aug 2026

Claude Opus 5Anthropiccurrent
Claude Fable 5Anthropiccurrent
3 slots left
SpecificationClaude Opus 5Claude Fable 5
SummaryComplex agentic coding and enterprise work at half the cost of Fable 5.Most capable widely released model, for the hardest reasoning and long-horizon agentic work.
Context1M1M
Input ($/Mtok)$5$10
Output ($/Mtok)$25$50
LicenceProprietaryProprietary
Max output128K128K
Released24 Jul 2026—
Model IDclaude-opus-5claude-fable-5
CategoryLanguage ModelsLanguage Models
OfficialAnthropic ↗Anthropic ↗

Highlighted rows are where these differ.

Claude Opus 5

  • Thinking on by default — a step change over Opus 4.8
  • 512-token prompt-cache minimum, down from 1024
  • Separate rate-limit bucket from the Opus 4.x pool

Best for agentic coding.

Full spec sheet →

Claude Fable 5

  • Thinking is always on — the `thinking` param is rejected
  • Raw chain of thought is never returned
  • Requires 30-day data retention; unavailable under ZDR

Best for the hardest problems.

Full spec sheet →