Claude Opus 5 vs OpenAI o3
Compare Claude Opus 5 by Anthropic against OpenAI o3 by OpenAI, tested across 53 shared challenges.
Our Verdict
Claude Opus 5
OpenAI o3
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 5
Input
$5.00
2.0× cheaper
Output
$25.00
1.6× cheaper
OpenAI o3
Input
$10.00
Output
$40.00
Claude Opus 5 is cheaper on both — 2.0× input, 1.6× output
Writing DNA
Style Comparison
Similarity
62%
Claude Opus 5 uses 1.7x more emoji
Claude Opus 5
OpenAI o3
54%Vocabulary68%
21wSentence Length14w
0.40Hedging0.26
3.9Bold0.7
1.9Lists3.0
0.02Emoji0.00
0.71Headings0.38
0.05Transitions0.12
Based on 27 + 16 text responses
Research
What we learned reading every model
FAQ
