What is the difference between Claude Opus 4.8 and GPT-5 Codex?

Claude Opus 4.8 is developed by Anthropic while GPT-5 Codex is developed by OpenAI. You can compare their actual outputs across 49 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4.8 or GPT-5 Codex?

It depends on your use case. Claude Opus 4.8 and GPT-5 Codex each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 49 challenges so you can judge which fits your needs best.

How can I compare Claude Opus 4.8 and GPT-5 Codex on Rival?

This page shows a side-by-side comparison of Claude Opus 4.8 and GPT-5 Codex across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

What is the difference between Claude Opus 4.8 and GPT-5 Codex?

Claude Opus 4.8 is developed by Anthropic while GPT-5 Codex is developed by OpenAI. You can compare their actual outputs across 49 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4.8 or GPT-5 Codex?

It depends on your use case. Claude Opus 4.8 and GPT-5 Codex each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 49 challenges so you can judge which fits your needs best.

How can I compare Claude Opus 4.8 and GPT-5 Codex on Rival?

This page shows a side-by-side comparison of Claude Opus 4.8 and GPT-5 Codex across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Claude Opus 4.8 vs GPT-5 Codex: Which Is Better?

Updated May 2026

Our Verdict

Claude Opus 4.8

GPT-5 Codex

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

API pricing

Cost per 1M tokens

Claude Opus 4.8

Input

$5.00

Output

$25.00

GPT-5 Codex

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

54%

Claude Opus 4.8 uses 5.3x more emoji

Claude Opus 4.8

GPT-5 Codex

60%Vocabulary64%

19wSentence Length17w

0.46Hedging0.38

4.7Bold2.3

3.2Lists3.5

0.78Emoji0.15

1.15Headings0.49

0.04Transitions0.05

Based on 27 + 13 text responses

Research

What we learned reading every model

Claude Opus 4.8 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 M3New provider

Claude Opus 4.8 vs Grok 3New provider

Claude Opus 4.8 vs Llama 4 MaverickNew provider

Updated May 2026

Our Verdict

Claude Opus 4.8

GPT-5 Codex

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

API pricing

Cost per 1M tokens

Claude Opus 4.8

Input

$5.00

Output

$25.00

GPT-5 Codex

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

54%

Claude Opus 4.8 uses 5.3x more emoji

Claude Opus 4.8

GPT-5 Codex

60%Vocabulary64%

19wSentence Length17w

0.46Hedging0.38

4.7Bold2.3

3.2Lists3.5

0.78Emoji0.15

1.15Headings0.49

0.04Transitions0.05

Based on 27 + 13 text responses

Research

What we learned reading every model

Claude Opus 4.8 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 M3New provider

Claude Opus 4.8 vs Grok 3New provider

Claude Opus 4.8 vs Llama 4 MaverickNew provider