What is the difference between GPT-5.1 Codex Max and OpenAI o3?

Both are developed by OpenAI but target different use cases. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, GPT-5.1 Codex Max or OpenAI o3?

It depends on your use case. GPT-5.1 Codex Max 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 can I compare GPT-5.1 Codex Max and OpenAI o3 on Rival?

This page shows a side-by-side comparison of GPT-5.1 Codex Max 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.