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Pyyan / Compare / Claude Mythos 5 vs Claude Sonnet 5

Claude Mythos 5 vs Claude Sonnet 5

2 of 5

Language Models · verified 13 Aug 2026

Claude Mythos 5Anthropicpreview
Claude Sonnet 5Anthropiccurrent
3 slots left
SpecificationClaude Mythos 5Claude Sonnet 5
SummaryFable 5's capabilities via Project Glasswing.Near-Opus quality on coding and agentic work at Sonnet cost.
Context1M1M
Input ($/Mtok)$10$3
Output ($/Mtok)$50$15
LicenceProprietaryProprietary
Max output128K128K
Model IDclaude-mythos-5claude-sonnet-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 Sonnet 5

  • Adaptive thinking on by default
  • New tokenizer — roughly 30% more tokens for the same text
  • Introductory $2/$10 through 31 Aug 2026

Best for high-volume production.

Full spec sheet →