Claude Opus 5 vs DeepSeek V4 Flash
Compare Claude Opus 5 by Anthropic against DeepSeek V4 Flash by DeepSeek, context windows of 1.0M vs 1.0M, tested across 54 shared challenges.
Our Verdict
Claude Opus 5
DeepSeek V4 FlashRunner-up
No community votes yet. On paper, Claude Opus 5 has the edge — bigger model tier, newer.
DeepSeek V4 Flash is 89x 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
DeepSeek V4 Flash
Input
$0.14
36× cheaper
Output
$0.28
89× cheaper
DeepSeek V4 Flash is cheaper on both — 36× input, 89× output
Writing DNA
Style Comparison
Similarity
71%
Claude Opus 5 uses 1.7x more emoji
Claude Opus 5
DeepSeek V4 Flash
54%Vocabulary54%
21wSentence Length17w
0.40Hedging0.52
3.9Bold3.6
1.9Lists2.6
0.02Emoji0.00
0.71Headings0.41
0.05Transitions0.19
Based on 27 + 27 text responses
Research
What we learned reading every model
FAQ
