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Pyyan / Compare / Gemini 3.8 Live Extended Thinking vs Claude Opus 5.5

Gemini 3.8 Live Extended Thinking vs Claude Opus 5.5

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Language Models · verified 24 Sept 2026

Gemini 3.8 Live Extended ThinkingGooglecurrent
Claude Opus 5.5Anthropiccurrent
3 slots left
SpecificationGemini 3.8 Live Extended ThinkingClaude Opus 5.5
SummaryTop of the speech to speech board, and it reasons out loud while it gets there.Fable 5.1's level of work on most tasks, at 40% less to run than Opus 5.
ContextNot published1M
Input ($/Mtok)$0.75$4
Output ($/Mtok)$4.5$20
LicenceProprietaryProprietary
Max outputNot published128K
ParametersNot publishedNot published
Released15 Sep 202622 Sep 2026
Model IDgemini-3.8-live-extended-thinkingclaude-opus-5-5
CategoryLanguage ModelsLanguage Models
OfficialGoogle ↗Anthropic ↗

Highlighted rows are where these differ.

Gemini 3.8 Live Extended Thinking

  • First on the Artificial Analysis Speech to Speech Quality Index at 82.6
  • 68.6% on tau-Voice and 97.7% on Big Bench Audio, both reported by Google
  • Speaks while it reasons, with cues such as let me check that

Best for hard tasks done by voice.

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 →