Z.ai: GLM 5.1 vs GPT OSS 120B
Compare Z.ai: GLM 5.1 by Z-ai against GPT OSS 120B by OpenAI, context windows of 203K vs 131K, tested across 52 shared challenges. Updated April 2026.
Which is better, Z.ai: GLM 5.1 or GPT OSS 120B?
Z.ai: GLM 5.1 and GPT OSS 120B are both competitive models. Z.ai: GLM 5.1 costs $1.4/M input tokens vs $0.18/M for GPT OSS 120B. Context windows: 203K vs 131K tokens. Compare their real outputs side by side below.
Key Differences Between Z.ai: GLM 5.1 and GPT OSS 120B
Z.ai: GLM 5.1 is made by z-ai while GPT OSS 120B is from openai. Z.ai: GLM 5.1 has a 203K token context window compared to GPT OSS 120B's 131K. On pricing, Z.ai: GLM 5.1 costs $1.4/M input tokens vs $0.18/M for GPT OSS 120B.
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
GPT OSS 120B is 5.5x cheaper per token — worth considering if cost matters.
Style Comparison
GPT OSS 120B uses 15.4x more emoji
vsAsk them anything yourself
Some models write identically. You are paying for the brand.
178 models fingerprinted across 32 writing dimensions. Free research.
185x
price gap between models that write identically
178
models
12
clone pairs
32
dimensions
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.
