What is the difference between Claude Opus 5 and OpenAI o3?

Claude Opus 5 is developed by Anthropic while OpenAI o3 is developed by OpenAI. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 5 or OpenAI o3?

It depends on your use case. Claude Opus 5 and OpenAI o3 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Opus 5 cost compared to OpenAI o3?

Claude Opus 5 costs $5/M input tokens and OpenAI o3 costs $10/M input tokens. Claude Opus 5 is $5.00/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Claude Opus 5 and OpenAI o3 on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and OpenAI o3 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.

Updated Jul 2026

Claude Opus 5vsOpenAI o3

Claude Opus 5 is cheaper than OpenAI o3 at $5/M vs $10/M input tokens.

Claude Opus 5 and OpenAI o3 compared across 53 shared prompts
Spec	Claude Opus 5	OpenAI o3
Input price	$5/M tokens	$10/M tokens
Output price	$25/M tokens	$40/M tokens
Context window	1.0M tokens	—
Weights	Closed	Closed
Free API (OpenRouter)	No	No
Released	Jul 2026	Apr 2025