OpenAI Codex Mini vs GPT-5 Codex

Compare OpenAI Codex Mini and GPT-5 Codex, both from OpenAI, tested across 9 shared challenges. Updated April 2026.

Which is better, OpenAI Codex Mini or GPT-5 Codex?

OpenAI Codex Mini and GPT-5 Codex are both competitive models. Compare their real outputs side by side below.

Key Differences Between OpenAI Codex Mini and GPT-5 Codex

OpenAI Codex Mini is made by openai while GPT-5 Codex is from openai.

Our Verdict
GPT-5 Codex
GPT-5 Codex
OpenAI Codex Mini
OpenAI Codex MiniRunner-up

No community votes yet. On paper, GPT-5 Codex has the edge — bigger model tier, newer.

Too close to call
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OpenAI Codex MiniGPT-5 Codex

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

AI Hallucination Index 2026
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