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Pyyan / Compare / Grok 4.5 vs Claude Opus 5

Grok 4.5 vs Claude Opus 5

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Language Models · verified 13 Aug 2026

Grok 4.5xAIcurrent
Claude Opus 5Anthropiccurrent
3 slots left
SpecificationGrok 4.5Claude Opus 5
SummaryOpus-class performance at lower cost.Complex agentic coding and enterprise work at half the cost of Fable 5.
Context500K1M
Input ($/Mtok)$2$5
Output ($/Mtok)$6$25
LicenceProprietaryProprietary
Max output—128K
Released—24 Jul 2026
Model IDgrok-4.5claude-opus-5
CategoryLanguage ModelsLanguage Models
OfficialxAI ↗Anthropic ↗

Highlighted rows are where these differ.

Grok 4.5

Opus-class performance at lower cost.

Best for value.

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 →