What is the difference between Claude Opus 5 and OpenAI o4-mini?

Claude Opus 5 is developed by Anthropic while OpenAI o4-mini is developed by OpenAI. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 5 or OpenAI o4-mini?

It depends on your use case. Claude Opus 5 and OpenAI o4-mini each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Opus 5 cost compared to OpenAI o4-mini?

Claude Opus 5 costs $5/M input tokens and OpenAI o4-mini costs $1.1/M input tokens. OpenAI o4-mini is $3.90/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Claude Opus 5 and OpenAI o4-mini on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and OpenAI o4-mini 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 5 and OpenAI o4-mini?

Claude Opus 5 is developed by Anthropic while OpenAI o4-mini is developed by OpenAI. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 5 or OpenAI o4-mini?

It depends on your use case. Claude Opus 5 and OpenAI o4-mini each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Opus 5 cost compared to OpenAI o4-mini?

Claude Opus 5 costs $5/M input tokens and OpenAI o4-mini costs $1.1/M input tokens. OpenAI o4-mini is $3.90/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Claude Opus 5 and OpenAI o4-mini on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and OpenAI o4-mini 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 5 vs OpenAI o4-mini: Which Is Better?

Updated Jul 2026

Our Verdict

Claude Opus 5

OpenAI o4-miniRunner-up

No community votes yet. On paper, Claude Opus 5 has the edge — bigger model tier, newer, bigger context window.

OpenAI o4-mini is 5.7x cheaper per token — worth considering if cost matters.

Too close to call

API pricing

Cost per 1M tokens

Claude Opus 5

Input

$5.00

Output

$25.00

OpenAI o4-mini

Input

$1.10

4.5× cheaper

Output

$4.40

5.7× cheaper

OpenAI o4-mini is cheaper on both — 4.5× input, 5.7× output

Writing DNA

Style Comparison

Similarity

61%

Claude Opus 5 uses 394.1x more bold

Claude Opus 5

OpenAI o4-mini

54%Vocabulary73%

21wSentence Length15w

0.40Hedging0.18

3.9Bold0.0

1.9Lists2.1

0.02Emoji0.00

0.71Headings0.00

0.05Transitions0.02

Based on 27 + 10 text responses

Research

What we learned reading every model

Claude Opus 5 and OpenAI o4-mini 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

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OpenAI o4-mini vs Gemini 2.5 Pro Preview 06-05New provider

OpenAI o4-mini vs Claude Opus 4Cross-provider

Updated Jul 2026

Our Verdict

Claude Opus 5

OpenAI o4-miniRunner-up

No community votes yet. On paper, Claude Opus 5 has the edge — bigger model tier, newer, bigger context window.

OpenAI o4-mini is 5.7x cheaper per token — worth considering if cost matters.

Too close to call

API pricing

Cost per 1M tokens

Claude Opus 5

Input

$5.00

Output

$25.00

OpenAI o4-mini

Input

$1.10

4.5× cheaper

Output

$4.40

5.7× cheaper

OpenAI o4-mini is cheaper on both — 4.5× input, 5.7× output

Writing DNA

Style Comparison

Similarity

61%

Claude Opus 5 uses 394.1x more bold

Claude Opus 5

OpenAI o4-mini

54%Vocabulary73%

21wSentence Length15w

0.40Hedging0.18

3.9Bold0.0

1.9Lists2.1

0.02Emoji0.00

0.71Headings0.00

0.05Transitions0.02

Based on 27 + 10 text responses

Research

What we learned reading every model

Claude Opus 5 and OpenAI o4-mini 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

OpenAI o4-mini vs MiniMax M3New provider

OpenAI o4-mini vs Gemini 2.5 Pro Preview 06-05New provider

OpenAI o4-mini vs Claude Opus 4Cross-provider