Claude Sonnet 4 vs GPT-5.1 Chat
Compare Claude Sonnet 4 by Anthropic against GPT-5.1 Chat by OpenAI, context windows of 200K vs 128K, tested across 53 shared challenges.
Our Verdict
Claude Sonnet 4
GPT-5.1 Chat
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 Sonnet 4
Input
$3.00
Output
$15.00
GPT-5.1 Chat
Input
$1.25
2.4× cheaper
Output
$10.00
1.5× cheaper
GPT-5.1 Chat is cheaper on both — 2.4× input, 1.5× output
Writing DNA
Style Comparison
Similarity
38%
Claude Sonnet 4 uses 87.9x more emoji
Claude Sonnet 4
GPT-5.1 Chat
62%Vocabulary73%
111wSentence Length18w
0.40Hedging0.45
5.0Bold1.1
9.3Lists2.4
0.88Emoji0.00
2.16Headings0.00
0.33Transitions0.06
Based on 17 + 15 text responses
Research
What we learned reading every model
FAQ
