Claude Sonnet 5 vs GPT-5.6 Terra: pricing, Quality, Value, and benchmarks

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Pricing, app access, and Conversation Value

• Humanity's Last Exam

  Normalized quality input

  43.2%

  Anthropic Claude Sonnet 5 system card | Vendor-reported Anthropic Sonnet 5 HLE no-tools score. Do not replace with tools-enabled HLE variants.

• SWE-Bench Pro

  Software engineering task resolution

  63.2%

  Anthropic Claude Sonnet 5 system card | Vendor-reported Anthropic Sonnet 5 SWE-Bench Pro score. Do not substitute SWE-Bench Verified.

• Terminal-Bench 2.1

  Agentic terminal task completion

  80.4%

  Anthropic Claude Sonnet 5 system card | Vendor-reported Anthropic Sonnet 5 Terminal-Bench 2.1 score using mini-SWE-agent. Display-only companion evidence.

• AA-Omniscience

  AA-Omniscience Index

  15.3

  Artificial Analysis AA-Omniscience evaluation | Independent Artificial Analysis result for Claude Sonnet 5 (max). Display-only; this row does not affect Quality or Value scores.

• Humanity's Last Exam

  Normalized quality input

  41.8%

  Artificial Analysis GPT-5.6 Terra max analysis page | Independent Artificial Analysis HLE result for the max-reasoning model variant. Treat as tier-3 provisional evidence and do not describe it as OpenAI-published no-tools HLE.

• AA-Omniscience

  AA-Omniscience Index

  -0.2

  Artificial Analysis AA-Omniscience evaluation | Independent Artificial Analysis result for GPT-5.6 Terra (max). Display-only; this row does not affect Quality or Value scores.

• SWE-Bench Pro

  Normalized quality input

  63.4%

  OpenAI GPT-5.6 release | OpenAI official GPT-5.6 launch table. Results are vendor-reported and must retain the named model tier, reasoning setting, benchmark version, and harness caveats.

• Terminal-Bench 2.1

  Agentic terminal task completion

  87.4%

  OpenAI GPT-5.6 announcement | OpenAI vendor-reported GPT-5.6 Terra Terminal-Bench 2.1 result. Do not substitute Sol, Luna, or another evaluation tier.

Ship Claude Sonnet 5 as the default Sonnet upgrade for production coding, agentic, and long-context workloads; budget for the September price step-up and reserve Opus for tasks that justify the higher tier.

Claude Sonnet 5 is the right default Sonnet model for most production teams that want stronger coding, agentic, and multi-step performance without moving every workload to Opus. It replaces Sonnet 4.6 in the current Claude lineup, carries stronger accepted-source HLE and SWE-Bench Pro evidence, and adds a 1M token context window that materially improves RAG, repository-scale coding, and document-heavy workflows. The migration still deserves an engineering review: the public row uses Anthropic vendor-reported benchmark evidence, the introductory API price ends after August 31, 2026, and plan-level availability or limits can vary by Claude surface. Treat it as the new default, test your real prompts and retrieval payloads, and route to Opus only when the task genuinely needs the higher-cost tier.

The balanced GPT-5.6 option for everyday work, trading some peak capability for lower cost.

GPT-5.6 Terra is the balanced tier for everyday professional and coding workloads. It gives up some peak performance versus Sol in exchange for lower token pricing, making it the practical default when both capability and cost matter.