Claude Fable 5.1 vs Claude Opus 5: pricing, Quality, Value, and benchmarks

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Pricing, app access, and Conversation Value

• Humanity's Last Exam

  Normalized quality input

  59.1%

  Artificial Analysis Claude Fable 5.1 evaluation | Independent HLE result using adaptive reasoning at maximum effort with Anthropic default safeguard fallback.

• SWE-Bench Pro

  Normalized quality input

  81.2%

  Anthropic Claude Fable 5.1 and Mythos 5.1 system card | Vendor-reported SWE-Bench Pro result using adaptive thinking at maximum effort and default sampling settings.

• Terminal-Bench 2.1

  Agentic terminal task completion

  91.4%

  Artificial Analysis Claude Fable 5.1 analysis | Independent Terminal-Bench 2.1 result using adaptive reasoning at maximum effort with default safeguard fallback.

• GPQA Diamond

  Normalized quality input

Anthropic's newest generally available Fable model leads the current scored evidence, with premium $10/$50 token pricing and safeguard fallback for some flagged requests.

Claude Fable 5.1 combines the strongest current locked-variant HLE and SWE-Bench Pro evidence with a 1M-token context window. Its $10 per million input-token and $50 per million output-token prices make it a specialist choice for difficult coding and knowledge work, while safeguard fallback means integrations should surface the model identity returned by the API.

Anthropic's Opus successor pairs frontier reasoning and coding results with premium $5/$25 token pricing.

Claude Opus 5 combines a 1M-token context window with strong exact-variant HLE and SWE-Bench Pro results. Its $5 per million input-token and $25 per million output-token prices keep it in the premium tier, so it is best reserved for work where capability matters more than unit cost.