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Pyyan / Compare / Claude Opus 4.8 vs Claude Opus 5

Claude Opus 4.8 vs Claude Opus 5

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Language Models · verified 13 Aug 2026

Claude Opus 4.8Anthropiccurrent
Claude Opus 5Anthropiccurrent
3 slots left
SpecificationClaude Opus 4.8Claude Opus 5
SummaryPrevious Opus flagship — warmer prose, strong long-horizon work.Complex agentic coding and enterprise work at half the cost of Fable 5.
Context1M1M
Input ($/Mtok)$5$5
Output ($/Mtok)$25$25
LicenceProprietaryProprietary
Max output128K128K
Released—24 Jul 2026
Model IDclaude-opus-4-8claude-opus-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 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 →