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Pyyan / Compare / Grok 4.6 vs Claude Opus 5.5

Grok 4.6 vs Claude Opus 5.5

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Language Models · verified 24 Sept 2026

Grok 4.6xAIcurrent
Claude Opus 5.5Anthropiccurrent
3 slots left
SpecificationGrok 4.6Claude Opus 5.5
SummaryNewest xAI flagship.Fable 5.1's level of work on most tasks, at 40% less to run than Opus 5.
Context500K1M
Input ($/Mtok)$2$4
Output ($/Mtok)$6$20
LicenceProprietaryProprietary
Max output—128K
Parameters—Not published
Released12 Aug 202622 Sep 2026
Model IDgrok-4.6claude-opus-5-5
CategoryLanguage ModelsLanguage Models
OfficialxAI ↗Anthropic ↗

Highlighted rows are where these differ.

Grok 4.6

  • Tiered pricing: doubles above 200K tokens
  • Smaller context than Grok 4.3 despite being newer

Best for cost-sensitive scale.

Full spec sheet →

Claude Opus 5.5

  • 66.4% on Terminal-Bench 4.0 against 52.3% for Opus 5, on Anthropic's own harness
  • Cache reads cut 60% to $0.20, and output more than 30% faster than Opus 5
  • Attempts to work around its boundaries 85% less often than Opus 5, Anthropic reports

Best for agentic coding at flagship quality.

Full spec sheet →