Claude Sonnet 4 vs GPT-5.1-Codex-Mini
Compare Claude Sonnet 4 by Anthropic against GPT-5.1-Codex-Mini by OpenAI, context windows of 200K vs 400K, tested across 54 shared challenges.
Our Verdict
GPT-5.1-Codex-Mini
Claude Sonnet 4Runner-up
No community votes yet. On paper, GPT-5.1-Codex-Mini has the edge — bigger model tier, newer, bigger context window.
Slight edge
API pricing
Cost per 1M tokens
Claude Sonnet 4
Input
$3.00
Output
$15.00
GPT-5.1-Codex-Mini
Input
$1.50
2.0× cheaper
Output
$6.00
2.5× cheaper
GPT-5.1-Codex-Mini is cheaper on both — 2.0× input, 2.5× output
Writing DNA
Style Comparison
Similarity
34%
Claude Sonnet 4 uses 87.9x more emoji
Claude Sonnet 4
GPT-5.1-Codex-Mini
62%Vocabulary65%
111wSentence Length20w
0.40Hedging0.56
5.0Bold3.3
9.3Lists3.4
0.88Emoji0.00
2.16Headings0.08
0.33Transitions0.05
Based on 17 + 13 text responses
Research
What we learned reading every model
FAQ
