Claude Opus 4.6 vs GPT-5.5 Pro

Compare Claude Opus 4.6 and GPT-5.5 Pro side by side. See pricing, capabilities, context length, and performance. Use both on Krater.ai from $20/mo.

Claude Opus 4.6 vs GPT-5.5 Pro: strengths, best use cases and how to run both side by side. The live page adds context windows, token pricing and more comparisons once it loads.

Try both on Krater

Run Claude Opus 4.6 and GPT-5.5 Pro on the same prompt in the Krater Model Arena, then keep the winner in your workflow. One subscription covers both, from $20 a month.

Open Krater chat · Claude Opus 4.6 on Krater · GPT-5.5 Pro on Krater

What each model is best at

Claude Opus 4.6

Anthropic's most powerful model ever. Claude Opus 4.6 delivers unparalleled reasoning depth, creative nuance, and coding capability with a 200K token context window.

Strengths

  • Deepest reasoning of any Claude model
  • Exceptional creative and analytical writing
  • Top-tier coding across all languages
  • Handles the most complex multi-step tasks

Best for

  • The most challenging intellectual tasks
  • Complex research and analysis
  • Professional creative writing
  • Enterprise-critical applications

GPT-5.5 Pro

OpenAI's GPT-5.5 Pro is the premium tier of GPT-5.5, with extended chain-of-thought reasoning for the hardest engineering, math, and research problems. 1M-token context, frontier accuracy.

Strengths

  • Extended thinking for hard problems
  • Top-tier code generation and refactoring
  • Frontier performance on math and science benchmarks
  • Long-context reasoning over entire codebases

Best for

  • Hard engineering and architectural questions
  • Research and scientific reasoning
  • Multi-step agentic tool use
  • Tasks where accuracy matters more than speed

How we compare models

Our tested head-to-heads run the same prompt set through both models in the Model Arena, then rank answers blind. Read the testing methodology, or browse every comparison.