Gemini 2.5 Flash Preview 05-20 (thinking) vs OpenAI o3
Compare Gemini 2.5 Flash Preview 05-20 (thinking) by Google AI against OpenAI o3 by OpenAI, tested across 12 shared challenges.
Our Verdict
Gemini 2.5 Flash Preview 05-20 (thinking)
OpenAI o3
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 11x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
Gemini 2.5 Flash Preview 05-20 (thinking)
Input
$0.15
67× cheaper
Output
$3.50
11× cheaper
OpenAI o3
Input
$10.00
Output
$40.00
Gemini 2.5 Flash Preview 05-20 (thinking) is cheaper on both — 67× input, 11× output
Writing DNA
Style Comparison
Similarity
53%
OpenAI o3 uses 26.0x more hedging
Gemini 2.5 Flash Preview 05-20 (thinking)
OpenAI o3
70%Vocabulary68%
11wSentence Length14w
0.00Hedging0.26
4.2Bold0.7
7.3Lists3.0
0.00Emoji0.00
0.00Headings0.38
0.00Transitions0.12
Based on 3 + 16 text responses
Research
What we learned reading every model
FAQ
