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Pyyan / Compare / Claude Mythos 5 vs Claude Opus 5

Claude Mythos 5 vs Claude Opus 5

2 of 5

Language Models · verified 13 Aug 2026

Claude Mythos 5Anthropicpreview
Claude Opus 5Anthropiccurrent
3 slots left
SpecificationClaude Mythos 5Claude Opus 5
SummaryFable 5's capabilities via Project Glasswing.Complex agentic coding and enterprise work at half the cost of Fable 5.
Context1M1M
Input ($/Mtok)$10$5
Output ($/Mtok)$50$25
LicenceProprietaryProprietary
Max output128K128K
Released—24 Jul 2026
Model IDclaude-mythos-5claude-opus-5
CategoryLanguage ModelsLanguage Models
OfficialAnthropic ↗Anthropic ↗

Highlighted rows are where these differ.

Claude Mythos 5

  • Same capabilities, pricing and API surface as Fable 5
  • Access only through Project Glasswing

Best for Glasswing participants.

Full spec sheet →

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 →