What is the difference between Claude Opus 4 and OpenAI Codex Mini?

Claude Opus 4 is developed by Anthropic while OpenAI Codex Mini is developed by OpenAI. Claude Opus 4 has a 200K token context window vs OpenAI Codex Mini's 200K. You can compare their actual outputs across 10 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4 or OpenAI Codex Mini?

It depends on your use case. Claude Opus 4 and OpenAI Codex Mini each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 10 challenges so you can judge which fits your needs best.

How much does Claude Opus 4 cost compared to OpenAI Codex Mini?

Claude Opus 4 costs $15/M input tokens and OpenAI Codex Mini costs $1.5/M input tokens. OpenAI Codex Mini is $13.50/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 4 and OpenAI Codex Mini on Rival?

This page shows a side-by-side comparison of Claude Opus 4 and OpenAI Codex Mini 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 May 2025

Claude Opus 4vsOpenAI Codex Mini

OpenAI Codex Mini is cheaper than Claude Opus 4 at $1.5/M vs $15/M input tokens.

Claude Opus 4 and OpenAI Codex Mini compared across 10 shared prompts
Spec	Claude Opus 4	OpenAI Codex Mini
Input price	$15/M tokens	$1.5/M tokens
Output price	$75/M tokens	$6/M tokens
Context window	200K tokens	200K tokens
Parameters	Not disclosed	Not disclosed
Weights	Closed	—
Free API (OpenRouter)	No	No
Released	May 2025	May 2025
SWE-bench Verified	72.5%	71.3%