What is the difference between Claude Opus 4 and GPT-5 Codex?

Claude Opus 4 is developed by Anthropic while GPT-5 Codex is developed by OpenAI. These results are based on blind head-to-head voting across 49 challenges.

Which is better, Claude Opus 4 or GPT-5 Codex?

Based on 4 community votes on Rival, Claude Opus 4 and GPT-5 Codex are closely matched with similar win rates. The better choice depends on your specific use case. Compare their real outputs side-by-side across 49 challenges to decide.

How are Claude Opus 4 vs GPT-5 Codex votes collected on Rival?

Rival presents both models' outputs side-by-side in blind duels. Voters see the responses but don't know which model produced each one, eliminating brand bias. 4 votes have been collected for this pair across 49 challenges. All vote data is part of Rival's open dataset.

What is the difference between Claude Opus 4 and GPT-5 Codex?

Claude Opus 4 is developed by Anthropic while GPT-5 Codex is developed by OpenAI. These results are based on blind head-to-head voting across 49 challenges.

Which is better, Claude Opus 4 or GPT-5 Codex?

Based on 4 community votes on Rival, Claude Opus 4 and GPT-5 Codex are closely matched with similar win rates. The better choice depends on your specific use case. Compare their real outputs side-by-side across 49 challenges to decide.

How are Claude Opus 4 vs GPT-5 Codex votes collected on Rival?

Rival presents both models' outputs side-by-side in blind duels. Voters see the responses but don't know which model produced each one, eliminating brand bias. 4 votes have been collected for this pair across 49 challenges. All vote data is part of Rival's open dataset.

Claude Opus 4 vs GPT-5 Codex: Which Is Better?

Updated Sep 2025

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

API pricing

Cost per 1M tokens

Claude Opus 4

Input

$15.00

Output

$75.00

GPT-5 Codex

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

31%

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

Research

What we learned reading every model

Claude Opus 4 and GPT-5 Codex have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

GPT-5 Codex vs MiniMax M1New provider

GPT-5 Codex vs Gemini 2.5 Pro Preview 06-05New provider

GPT-5 Codex vs Claude Sonnet 4Cross-provider

Updated Sep 2025

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

API pricing

Cost per 1M tokens

Claude Opus 4

Input

$15.00

Output

$75.00

GPT-5 Codex

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

31%

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

Research

What we learned reading every model

Claude Opus 4 and GPT-5 Codex have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

GPT-5 Codex vs MiniMax M1New provider

GPT-5 Codex vs Gemini 2.5 Pro Preview 06-05New provider

GPT-5 Codex vs Claude Sonnet 4Cross-provider