GPT-5 Pro vs GPT-5.3-Codex
Compare GPT-5 Pro and GPT-5.3-Codex, both from OpenAI, context windows of 400K vs 400K, tested across 41 shared challenges.
Our Verdict
GPT-5 Pro
GPT-5.3-Codex
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
GPT-5.3-Codex is 8.6x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
GPT-5 Pro
Input
$15.00
Output
$120.00
GPT-5.3-Codex
Input
$1.75
8.6× cheaper
Output
$14.00
8.6× cheaper
GPT-5.3-Codex is cheaper on both — 8.6× input, 8.6× output
Writing DNA
Style Comparison
Similarity
45%
GPT-5.3-Codex uses 654.6x more bold
GPT-5 Pro
GPT-5.3-Codex
65%Vocabulary65%
15wSentence Length23w
0.32Hedging0.51
0.0Bold6.5
2.9Lists6.2
0.00Emoji0.16
0.00Headings1.90
0.01Transitions0.03
Based on 11 + 23 text responses
Research
What we learned reading every model
FAQ
