Z.AI: GLM 4.5 Air vs Claude Opus 4

Compare Z.AI: GLM 4.5 Air by Zhipu AI against Claude Opus 4 by Anthropic, in 5 community votes, claude opus 4 wins 60% of head-to-head duels, context windows of 128K vs 200K, tested across 20 shared challenges. Updated April 2026.

Which is better, Z.AI: GLM 4.5 Air or Claude Opus 4?

Claude Opus 4 is the better choice overall, winning 60% of 5 blind community votes on Rival. Z.AI: GLM 4.5 Air costs $0.2/M input tokens vs $15/M for Claude Opus 4. Context windows: 128K vs 200K tokens. Compare their real outputs side by side below.

Key Differences Between Z.AI: GLM 4.5 Air and Claude Opus 4

Z.AI: GLM 4.5 Air is made by zhipu while Claude Opus 4 is from anthropic. Z.AI: GLM 4.5 Air has a 128K token context window compared to Claude Opus 4's 200K. On pricing, Z.AI: GLM 4.5 Air costs $0.2/M input tokens vs $15/M for Claude Opus 4. In community voting, In 5 community votes, Claude Opus 4 wins 60% of head-to-head duels.

In 5 community votes, Claude Opus 4 wins 60% of head-to-head duels. Claude Opus 4 leads in Image Generation. Based on blind community voting from the Rival open dataset of 5+ human preference judgments for this pair.

Image Generation: Claude Opus 4 wins 75% of votes
Our Verdict
Claude Opus 4
Claude Opus 4Winner
Z.AI: GLM 4.5 Air
Z.AI: GLM 4.5 AirRunner-up

Pick Claude Opus 4. In 5 blind votes, Claude Opus 4 wins 60% of the time. That's not luck.

Claude Opus 4 particularly excels in Image Generation. Z.AI: GLM 4.5 Air is 68x cheaper per token — worth considering if cost matters.

Clear winner
Writing DNA

Style Comparison

Similarity
90%

Claude Opus 4 uses 3.8x more sentence length

Z.AI: GLM 4.5 Air
Claude Opus 4
48%Vocabulary64%
16wSentence Length62w
0.40Hedging0.52
5.4Bold4.4
4.8Lists9.1
0.10Emoji0.11
0.75Headings1.87
0.12Transitions0.27
Based on 15 + 16 text responses
vs

Ask them anything yourself

Z.AI: GLM 4.5 AirClaude Opus 4

Some models write identically. You are paying for the brand.

178 models fingerprinted across 32 writing dimensions. Free research.

Model Similarity Index

185x

price gap between models that write identically

178

models

12

clone pairs

32

dimensions

Devstral M / S
95.7%
Qwen3 Coder / Flash
95.6%
GPT-5.4 / Mini
93.3%

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

AI Hallucination Index 2026
Free preview13 of 58 slides
FAQ

Common questions