GPT-5.3-Codex vs Kimi K2.6
Compare GPT-5.3-Codex by OpenAI against Kimi K2.6 by Moonshot AI, context windows of 400K vs 262K, tested across 53 shared challenges.
Our Verdict
GPT-5.3-Codex
Kimi K2.6Runner-up
No community votes yet. On paper, GPT-5.3-Codex has the edge — bigger model tier, bigger context window, major provider backing.
Kimi K2.6 is 3.5x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
GPT-5.3-Codex
Input
$1.75
Output
$14.00
Kimi K2.6
Input
$0.95
1.8× cheaper
Output
$4.00
3.5× cheaper
Kimi K2.6 is cheaper on both — 1.8× input, 3.5× output
Writing DNA
Style Comparison
Similarity
28%
Kimi K2.6 uses 5.7x more transitions
GPT-5.3-Codex
Kimi K2.6
65%Vocabulary57%
23wSentence Length16w
0.51Hedging0.37
6.5Bold4.3
6.2Lists2.0
0.16Emoji0.03
1.90Headings0.53
0.03Transitions0.16
Based on 23 + 27 text responses
Research
What we learned reading every model
FAQ
