GPT-5 Pro vs GPT-5.1-Codex
Compare GPT-5 Pro and GPT-5.1-Codex, both from OpenAI, context windows of 400K vs 400K, tested across 42 shared challenges.
Our Verdict
GPT-5 Pro
GPT-5.1-Codex
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
GPT-5.1-Codex is 12x 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-5.1-Codex
Input
$1.25
12× cheaper
Output
$10.00
12× cheaper
GPT-5.1-Codex is cheaper on both — 12× input, 12× output
Writing DNA
Style Comparison
Similarity
72%
GPT-5.1-Codex uses 343.9x more bold
GPT-5 Pro
GPT-5.1-Codex
65%Vocabulary70%
15wSentence Length17w
0.32Hedging0.39
0.0Bold3.4
2.9Lists3.5
0.00Emoji0.00
0.00Headings0.50
0.01Transitions0.38
Based on 11 + 14 text responses
Research
What we learned reading every model
FAQ
Common questions
Keep exploring
