Claude Opus 5.5vsGPT-5 Pro

Claude Opus 5.5 is developed by Anthropic while GPT-5 Pro is developed by OpenAI. Claude Opus 5.5 has a 1.0M token context window vs GPT-5 Pro's 400K. You can compare their actual outputs across 19 challenges on Rival to see how they differ in practice.

It depends on your use case. Claude Opus 5.5 and GPT-5 Pro each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 19 challenges so you can judge which fits your needs best.

Claude Opus 5.5 costs $4/M input tokens and GPT-5 Pro costs $15/M input tokens. Claude Opus 5.5 is $11.00/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

This page shows a side-by-side comparison of Claude Opus 5.5 and GPT-5 Pro across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.