Z.AI: GLM 4.5 Air vs GPT-5 Pro
Compare Z.AI: GLM 4.5 Air by Zhipu AI against GPT-5 Pro by OpenAI, context windows of 128K vs 400K, tested across 41 shared challenges.
Our Verdict
GPT-5 Pro
Z.AI: GLM 4.5 AirRunner-up
No community votes yet. On paper, GPT-5 Pro has the edge — bigger model tier, newer, bigger context window.
Z.AI: GLM 4.5 Air is 109x cheaper per token — worth considering if cost matters.
Slight edge
API pricing
Cost per 1M tokens
Z.AI: GLM 4.5 Air
Input
$0.20
75× cheaper
Output
$1.10
109× cheaper
GPT-5 Pro
Input
$15.00
Output
$120.00
Z.AI: GLM 4.5 Air is cheaper on both — 75× input, 109× output
Writing DNA
Style Comparison
Similarity
33%
Z.AI: GLM 4.5 Air uses 540.4x more bold
Z.AI: GLM 4.5 Air
GPT-5 Pro
48%Vocabulary65%
16wSentence Length15w
0.40Hedging0.32
5.4Bold0.0
4.8Lists2.9
0.10Emoji0.00
0.75Headings0.00
0.12Transitions0.01
Based on 15 + 11 text responses
Research
What we learned reading every model
FAQ
