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Pyyan / Compare / Claude Opus 4.8 vs Claude Sonnet 5

Claude Opus 4.8 vs Claude Sonnet 5

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Language Models · verified 13 Aug 2026

Claude Opus 4.8Anthropiccurrent
Claude Sonnet 5Anthropiccurrent
3 slots left
SpecificationClaude Opus 4.8Claude Sonnet 5
SummaryPrevious Opus flagship — warmer prose, strong long-horizon work.Near-Opus quality on coding and agentic work at Sonnet cost.
Context1M1M
Input ($/Mtok)$5$3
Output ($/Mtok)$25$15
LicenceProprietaryProprietary
Max output128K128K
Model IDclaude-opus-4-8claude-sonnet-5
CategoryLanguage ModelsLanguage Models
OfficialAnthropic ↗Anthropic ↗

Highlighted rows are where these differ.

Claude Opus 4.8

  • Mid-session system messages supported
  • Adaptive thinking only — budget_tokens removed

Best for long-horizon agents.

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 →