Gemini 2.5 Flash Preview (thinking) vs Gemini 3.1 Pro Preview
Compare Gemini 2.5 Flash Preview (thinking) and Gemini 3.1 Pro Preview, both from Google AI, context windows of 1.0M vs 1.0M, tested across 20 shared challenges.
Our Verdict
Gemini 3.1 Pro Preview
Gemini 2.5 Flash Preview (thinking)Runner-up
No community votes yet. On paper, Gemini 3.1 Pro Preview has the edge — bigger model tier, newer.
Gemini 2.5 Flash Preview (thinking) is 3.4x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
Gemini 2.5 Flash Preview (thinking)
Input
$0.17
11× cheaper
Output
$3.50
3.4× cheaper
Gemini 3.1 Pro Preview
Input
$2.00
Output
$12.00
Gemini 2.5 Flash Preview (thinking) is cheaper on both — 11× input, 3.4× output
Writing DNA
Style Comparison
Similarity
70%
Gemini 3.1 Pro Preview uses 71.7x more headings
Gemini 2.5 Flash Preview (thinking)
Gemini 3.1 Pro Preview
53%Vocabulary54%
14wSentence Length18w
0.38Hedging0.29
4.4Bold4.9
4.1Lists3.3
0.00Emoji0.00
0.00Headings0.72
0.24Transitions0.14
Based on 7 + 23 text responses
Research
What we learned reading every model
FAQ
