OpenAI Codex Mini vs Gemini 2.5 Pro (I/O Edition)

Compare OpenAI Codex Mini by OpenAI against Gemini 2.5 Pro (I/O Edition) by Google AI, in 9 community votes, openai codex mini and gemini 2.5 pro (i/o edition) are closely matched, tested across 10 shared challenges. Updated April 2026.

Which is better, OpenAI Codex Mini or Gemini 2.5 Pro (I/O Edition)?

OpenAI Codex Mini and Gemini 2.5 Pro (I/O Edition) are closely matched based on 9 community votes. OpenAI Codex Mini costs $1.5/M input tokens vs $1.25/M for Gemini 2.5 Pro (I/O Edition). Compare their real outputs side by side below.

Key Differences Between OpenAI Codex Mini and Gemini 2.5 Pro (I/O Edition)

OpenAI Codex Mini is made by openai while Gemini 2.5 Pro (I/O Edition) is from google. On pricing, OpenAI Codex Mini costs $1.5/M input tokens vs $1.25/M for Gemini 2.5 Pro (I/O Edition). In community voting, In 9 community votes, OpenAI Codex Mini and Gemini 2.5 Pro (I/O Edition) are closely matched.

In 9 community votes, OpenAI Codex Mini and Gemini 2.5 Pro (I/O Edition) are closely matched. OpenAI Codex Mini leads in Web Design, while Gemini 2.5 Pro (I/O Edition) leads in Image Generation. Based on blind community voting from the Rival open dataset of 9+ human preference judgments for this pair.

Image Generation: Gemini 2.5 Pro (I/O Edition) wins 100% of votes
Web Design: OpenAI Codex Mini wins 100% of votes
Our Verdict
OpenAI Codex Mini
OpenAI Codex Mini
Gemini 2.5 Pro (I/O Edition)
Gemini 2.5 Pro (I/O Edition)

Too close to call. Pick based on your use case.

Pick OpenAI Codex Mini for Web Design. Pick Gemini 2.5 Pro (I/O Edition) for Image Generation.

Too close to call
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OpenAI Codex MiniGemini 2.5 Pro (I/O Edition)

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