Claude Sonnet 4 vs Gemini 2.5 Flash Preview 05-20 (thinking)
Compare Claude Sonnet 4 by Anthropic against Gemini 2.5 Flash Preview 05-20 (thinking) by Google AI, context windows of 200K vs 1.0M, tested across 12 shared challenges.
Our Verdict
Claude Sonnet 4
Gemini 2.5 Flash Preview 05-20 (thinking)
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
Gemini 2.5 Flash Preview 05-20 (thinking) is 4.3x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
Claude Sonnet 4
Input
$3.00
Output
$15.00
Gemini 2.5 Flash Preview 05-20 (thinking)
Input
$0.15
20× cheaper
Output
$3.50
4.3× cheaper
Gemini 2.5 Flash Preview 05-20 (thinking) is cheaper on both — 20× input, 4.3× output
Writing DNA
Style Comparison
Similarity
46%
Claude Sonnet 4 uses 40.1x more hedging
Claude Sonnet 4
Gemini 2.5 Flash Preview 05-20 (thinking)
62%Vocabulary70%
111wSentence Length11w
0.40Hedging0.00
5.0Bold4.2
9.3Lists7.3
0.88Emoji0.00
2.16Headings0.00
0.33Transitions0.00
Based on 17 + 3 text responses
Research
What we learned reading every model
FAQ
