Z.ai: GLM 5.1 vs Gemini 2.5 Pro Preview 06-05

Compare Z.ai: GLM 5.1 by Z-ai against Gemini 2.5 Pro Preview 06-05 by Google AI, context windows of 203K vs 1.0M, tested across 38 shared challenges. Updated April 2026.

Which is better, Z.ai: GLM 5.1 or Gemini 2.5 Pro Preview 06-05?

Z.ai: GLM 5.1 and Gemini 2.5 Pro Preview 06-05 are both competitive models. Z.ai: GLM 5.1 costs $1.4/M input tokens vs $1.25/M for Gemini 2.5 Pro Preview 06-05. Context windows: 203K vs 1049K tokens. Compare their real outputs side by side below.

Key Differences Between Z.ai: GLM 5.1 and Gemini 2.5 Pro Preview 06-05

Z.ai: GLM 5.1 is made by z-ai while Gemini 2.5 Pro Preview 06-05 is from google. Z.ai: GLM 5.1 has a 203K token context window compared to Gemini 2.5 Pro Preview 06-05's 1049K. On pricing, Z.ai: GLM 5.1 costs $1.4/M input tokens vs $1.25/M for Gemini 2.5 Pro Preview 06-05.

Our Verdict
Gemini 2.5 Pro Preview 06-05
Gemini 2.5 Pro Preview 06-05
Z.ai: GLM 5.1
Z.ai: GLM 5.1Runner-up

No community votes yet. On paper, Gemini 2.5 Pro Preview 06-05 has the edge — bigger model tier, bigger context window, major provider backing.

Too close to call
Writing DNA

Style Comparison

Similarity
97%

Gemini 2.5 Pro Preview 06-05 uses 2.3x more headings

Z.ai: GLM 5.1
Gemini 2.5 Pro Preview 06-05
54%Vocabulary51%
18wSentence Length15w
0.31Hedging0.31
3.6Bold4.8
2.6Lists4.1
0.00Emoji0.00
0.43Headings0.98
0.11Transitions0.05
Based on 27 + 20 text responses
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Z.ai: GLM 5.1Gemini 2.5 Pro Preview 06-05

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185x

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