Claude Opus 4.8 vs GPT-5.6 Sol: pricing, Quality, Value, and benchmarks

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Pricing, app access, and Conversation Value

• Humanity's Last Exam

  Normalized quality input

  49.8%

  Anthropic Claude Opus 4.8 release page | Vendor-reported Anthropic Opus 4.8 HLE no-tools score. Do not replace with tools-enabled or adaptive-effort HLE variants.

• SWE-Bench Pro

  Software engineering task resolution

  69.2%

  Anthropic Claude Opus 4.8 release page | Vendor-reported Anthropic Opus 4.8 SWE-Bench Pro score. Do not substitute SWE-Bench Verified.

• Humanity's Last Exam

  Normalized quality input

  47.2%

  Artificial Analysis GPT-5.6 Sol max analysis page | Independent Artificial Analysis HLE result for the max-reasoning model variant. This is provisional tier-3 evidence, not an OpenAI-published no-tools HLE result.

• SWE-Bench Pro

  Software engineering task resolution

  64.6%

  OpenAI GPT-5.6 release | Vendor-reported OpenAI GPT-5.6 launch result. Preserve the named tier and launch configuration; do not substitute a similarly named benchmark or model variant.

• GPQA Diamond

  Graduate-level scientific reasoning

  94.6%

  OpenAI GPT-5.6 release | Vendor-reported OpenAI GPT-5.6 launch result. Preserve the named tier and launch configuration; do not substitute a similarly named benchmark or model variant.

• Terminal-Bench 2.1

  Agentic terminal task completion

  88.8%

  OpenAI GPT-5.6 release | Vendor-reported OpenAI GPT-5.6 launch result. Preserve the named tier and launch configuration; do not substitute a similarly named benchmark or model variant.

Claude Opus 4.8 is Anthropic's newest Opus model, strongest for coding, agentic tasks, and complex professional work where the vendor-reported benchmark evidence applies.

Released May 28, 2026, Claude Opus 4.8 is Anthropic's current flagship and its most capable publicly available model. It is best suited to complex agentic coding, legal and financial document analysis, deep multi-step reasoning, and long-running autonomous tasks. The meaningful upgrades over 4.7 are a dramatic improvement in mathematical reasoning, meaningfully better honesty (it flags its own mistakes rather than quietly moving on), and efficiency gains that mean it uses around 35% fewer output tokens to do the same work — so you actually get a little more for your money despite the unchanged rate card. The honest caveats: it is expensive at $25 per million output tokens, which adds up fast on any high-volume or long-session workflow. On claude.ai, users now have control over the amount of effort Claude puts into a task, but Pro plan rate limits are real and noticeable if you push it hard — heavy users will hit the ceiling. It is also slower than average at inference speed, so it thinks longer before responding. For chat, summarisation, and general Q&A, Sonnet 4.6 covers 90%+ of workloads at 40% lower per-token cost — most buyers do not need Opus for everyday tasks. AnthropicFinout Bottom line: Opus 4.8 is genuinely the best model for serious, sustained, complex work. It is overkill and quietly costly for anything routine — and if you hit the rate limits on a Pro plan, the frustration will feel disproportionate to what you are paying.

OpenAI’s flagship for complex professional work and coding, at premium API pricing.

GPT-5.6 Sol is OpenAI’s flagship tier for complex coding and professional work. Its strong independent HLE and official SWE-Bench Pro evidence come with the family’s highest API price, so it is best reserved for work that justifies maximum capability.