Gemini 2.5 Flash Preview vs Gemini 2.5 Pro (I/O Edition)
Compare Gemini 2.5 Flash Preview and Gemini 2.5 Pro (I/O Edition), both from Google AI, tested across 21 shared challenges.
Our Verdict
Gemini 2.5 Pro (I/O Edition)
Gemini 2.5 Flash PreviewRunner-up
No community votes yet. On paper, Gemini 2.5 Pro (I/O Edition) has the edge — bigger model tier.
Gemini 2.5 Flash Preview is 17x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
Gemini 2.5 Flash Preview
Input
$0.15
8.3× cheaper
Output
$0.60
17× cheaper
Gemini 2.5 Pro (I/O Edition)
Input
$1.25
Output
$10.00
Gemini 2.5 Flash Preview is cheaper on both — 8.3× input, 17× output
Writing DNA
Style Comparison
Similarity
46%
Gemini 2.5 Flash Preview uses 20.1x more transitions
Gemini 2.5 Flash Preview
Gemini 2.5 Pro (I/O Edition)
51%Vocabulary58%
15wSentence Length16w
0.70Hedging0.38
4.1Bold5.8
3.3Lists5.0
0.00Emoji0.00
0.09Headings0.63
0.24Transitions0.01
Based on 12 + 16 text responses
Research
What we learned reading every model
FAQ
