GPT-5 Codex
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GPT-5 Codex vs Claude Opus 4
Compare GPT-5 Codex by OpenAI against Claude Opus 4 by Anthropic, in 4 community votes, gpt-5 codex and claude opus 4 are closely matched, tested across 31 shared challenges. Updated April 2026.
Which is better, GPT-5 Codex or Claude Opus 4?
GPT-5 Codex and Claude Opus 4 are closely matched based on 4 community votes. Compare their real outputs side by side below.
Key Differences Between GPT-5 Codex and Claude Opus 4
GPT-5 Codex is made by openai while Claude Opus 4 is from anthropic. In community voting, In 4 community votes, GPT-5 Codex and Claude Opus 4 are closely matched.
In 4 community votes, GPT-5 Codex and Claude Opus 4 are closely matched. Claude Opus 4 leads in Web Design. Based on blind community voting from the Rival open dataset of 4+ human preference judgments for this pair.
Web Design: Claude Opus 4 wins 67% of votes
Our Verdict
GPT-5 CodexWinner
Claude Opus 4Runner-up
Votes are tied. GPT-5 Codex is newer and likely incorporates more recent improvements.
Claude Opus 4 particularly excels in Web Design.
Too close to call
Writing DNA
Style Comparison
Similarity
93%
Claude Opus 4 uses 5.0x more transitions
GPT-5 Codex
Claude Opus 4
64%Vocabulary64%
17wSentence Length62w
0.38Hedging0.52
2.3Bold4.4
3.5Lists9.1
0.15Emoji0.11
0.49Headings1.87
0.05Transitions0.27
Based on 13 + 16 text responses
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