Gemini 3 Flash Preview vs GPT-5.3-Codex
Compare Gemini 3 Flash Preview by Google AI against GPT-5.3-Codex by OpenAI, context windows of 1.0M vs 400K, tested across 53 shared challenges.
Our Verdict
GPT-5.3-Codex
Gemini 3 Flash PreviewRunner-up
No community votes yet. On paper, GPT-5.3-Codex has the edge — bigger model tier, newer.
Gemini 3 Flash Preview is 4.7x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
Gemini 3 Flash Preview
Input
$0.50
3.5× cheaper
Output
$3.00
4.7× cheaper
GPT-5.3-Codex
Input
$1.75
Output
$14.00
Gemini 3 Flash Preview is cheaper on both — 3.5× input, 4.7× output
Writing DNA
Style Comparison
Similarity
50%
GPT-5.3-Codex uses 15.8x more emoji
Gemini 3 Flash Preview
GPT-5.3-Codex
55%Vocabulary65%
18wSentence Length23w
0.42Hedging0.51
7.1Bold6.5
4.5Lists6.2
0.00Emoji0.16
0.84Headings1.90
0.07Transitions0.03
Based on 24 + 23 text responses
Research
What we learned reading every model
FAQ
