Claude Sonnet 4.5 vs GPT-4.5
Compare Claude Sonnet 4.5 by Anthropic against GPT-4.5 by OpenAI, context windows of 200K vs 128K, tested across 22 shared challenges.
Our Verdict
Claude Sonnet 4.5
GPT-4.5
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
Claude Sonnet 4.5 is 10x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
Claude Sonnet 4.5
Input
$3.00
25× cheaper
Output
$15.00
10× cheaper
GPT-4.5
Input
$75.00
Output
$150.00
Claude Sonnet 4.5 is cheaper on both — 25× input, 10× output
Writing DNA
Style Comparison
Similarity
58%
Claude Sonnet 4.5 uses 45.2x more emoji
Claude Sonnet 4.5
GPT-4.5
64%Vocabulary63%
94wSentence Length16w
0.48Hedging0.57
4.9Bold4.7
8.0Lists6.4
0.45Emoji0.00
1.91Headings1.30
0.07Transitions0.54
Based on 20 + 11 text responses
Research
What we learned reading every model
FAQ
