Z.AI: GLM 4.5 vs GPT-5.5
Compare Z.AI: GLM 4.5 by Zhipu AI against GPT-5.5 by OpenAI, context windows of 128K vs 1.1M, tested across 54 shared challenges.
Our Verdict
GPT-5.5
Z.AI: GLM 4.5Runner-up
No community votes yet. On paper, GPT-5.5 has the edge — bigger model tier, newer, bigger context window.
Z.AI: GLM 4.5 is 14x cheaper per token — worth considering if cost matters.
Slight edge
API pricing
Cost per 1M tokens
Z.AI: GLM 4.5
Input
$0.60
8.3× cheaper
Output
$2.20
14× cheaper
GPT-5.5
Input
$5.00
Output
$30.00
Z.AI: GLM 4.5 is cheaper on both — 8.3× input, 14× output
Writing DNA
Style Comparison
Similarity
39%
Z.AI: GLM 4.5 uses 13.1x more emoji
Z.AI: GLM 4.5
GPT-5.5
52%Vocabulary58%
14wSentence Length18w
0.49Hedging0.74
5.5Bold2.9
4.9Lists5.1
0.13Emoji0.00
0.68Headings1.68
0.20Transitions0.03
Based on 21 + 26 text responses
Research
What we learned reading every model
FAQ
