What is the difference between Claude Opus 5 and o3 Mini?

Claude Opus 5 is developed by Anthropic while o3 Mini is developed by OpenAI. Claude Opus 5 has a 1.0M token context window vs o3 Mini's 64K. 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 o3 Mini?

It depends on your use case. Claude Opus 5 and o3 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 o3 Mini?

Claude Opus 5 costs $5/M input tokens and o3 Mini costs $1.1/M input tokens. o3 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 o3 Mini on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and o3 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 o3 Mini?

Claude Opus 5 is developed by Anthropic while o3 Mini is developed by OpenAI. Claude Opus 5 has a 1.0M token context window vs o3 Mini's 64K. 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 o3 Mini?

It depends on your use case. Claude Opus 5 and o3 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 o3 Mini?

Claude Opus 5 costs $5/M input tokens and o3 Mini costs $1.1/M input tokens. o3 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 o3 Mini on Rival?

This page shows a side-by-side comparison of Claude Opus 5 and o3 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 o3 Mini: Which Is Better?

Updated Jul 2026

Our Verdict

Claude Opus 5

o3 MiniRunner-up

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

o3 Mini is 5.7x cheaper per token — worth considering if cost matters.

Slight edge

API pricing

Cost per 1M tokens

Claude Opus 5

Input

$5.00

Output

$25.00

o3 Mini

Input

$1.10

4.5× cheaper

Output

$4.40

5.7× cheaper

o3 Mini is cheaper on both — 4.5× input, 5.7× output

Writing DNA

Style Comparison

Similarity

39%

Claude Opus 5 uses 1.7x more emoji

Claude Opus 5

o3 Mini

54%Vocabulary65%

21wSentence Length17w

0.40Hedging0.74

3.9Bold3.9

1.9Lists1.7

0.02Emoji0.00

0.71Headings0.47

0.05Transitions0.38

Based on 27 + 12 text responses

Research

What we learned reading every model

Claude Opus 5 and o3 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

o3 Mini vs MiniMax M3New provider

o3 Mini vs Gemini 2.5 Pro Preview 06-05New provider

o3 Mini vs Claude Opus 4Cross-provider

Updated Jul 2026

Our Verdict

Claude Opus 5

o3 MiniRunner-up

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

o3 Mini is 5.7x cheaper per token — worth considering if cost matters.

Slight edge

API pricing

Cost per 1M tokens

Claude Opus 5

Input

$5.00

Output

$25.00

o3 Mini

Input

$1.10

4.5× cheaper

Output

$4.40

5.7× cheaper

o3 Mini is cheaper on both — 4.5× input, 5.7× output

Writing DNA

Style Comparison

Similarity

39%

Claude Opus 5 uses 1.7x more emoji

Claude Opus 5

o3 Mini

54%Vocabulary65%

21wSentence Length17w

0.40Hedging0.74

3.9Bold3.9

1.9Lists1.7

0.02Emoji0.00

0.71Headings0.47

0.05Transitions0.38

Based on 27 + 12 text responses

Research

What we learned reading every model

Claude Opus 5 and o3 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

o3 Mini vs MiniMax M3New provider

o3 Mini vs Gemini 2.5 Pro Preview 06-05New provider

o3 Mini vs Claude Opus 4Cross-provider