Claude Opus 4
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Claude Opus 4 vs GPT-5 Codex
Compare Claude Opus 4 by Anthropic against GPT-5 Codex by OpenAI, in 4 community votes, claude opus 4 and gpt-5 codex are closely matched, tested across 31 shared challenges. Updated April 2026.
Which is better, Claude Opus 4 or GPT-5 Codex?
Claude Opus 4 and GPT-5 Codex are closely matched based on 4 community votes. Compare their real outputs side by side below.
Key Differences Between Claude Opus 4 and GPT-5 Codex
Claude Opus 4 is made by anthropic while GPT-5 Codex is from openai. In community voting, In 4 community votes, Claude Opus 4 and GPT-5 Codex are closely matched.
In 4 community votes, Claude Opus 4 and GPT-5 Codex 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
Claude Opus 4
GPT-5 Codex
64%Vocabulary64%
62wSentence Length17w
0.52Hedging0.38
4.4Bold2.3
9.1Lists3.5
0.11Emoji0.15
1.87Headings0.49
0.27Transitions0.05
Based on 16 + 13 text responses
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