GPT-4o mini vs GLM-4.5
OpenAI GPT-4o mini | Z.ai GLM-4.5 | |
|---|---|---|
| Overview | ||
| Company | OpenAI | Z.ai |
| Release date | Jul 18 2024 | Jul 28 2025 |
| Access | Proprietary | Open Weight |
| Specifications | ||
Parameters | — | 355B |
Context window | — | 128k |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | 2% | — |
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | — | 64.2% |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | — | 79.1% |
| Timeline | ||
| Release gap | GPT-4o mini shipped 375 days before GLM-4.5 | |
Which is better: GPT-4o mini or GLM-4.5?
GPT-4o mini and GLM-4.5 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. GPT-4o mini shipped 375 days before GLM-4.5, so benchmark comparisons should account for the intervening progress.
GPT-4o mini is proprietary, while GLM-4.5 is open weight.
Direct benchmark comparisons are unavailable — GPT-4o mini and GLM-4.5 don't publish scores on any of the same benchmarks.
Frequently asked questions
GPT-4o mini was released by OpenAI on Jul 18 2024.
GLM-4.5 was released by Z.ai on Jul 28 2025.
GPT-4o mini is a proprietary model released by OpenAI. GLM-4.5 is an open weight model released by Z.ai.
Other comparisons
GPT-4o mini vs Claude Fable 5GLM-4.5 vs Claude Fable 5GPT-4o mini vs Gemini OmniGLM-4.5 vs Gemini OmniGPT-4o mini vs Muse SparkGLM-4.5 vs Muse SparkGPT-4o mini vs Grok 4.3 BetaGLM-4.5 vs Grok 4.3 BetaGPT-4o mini vs DeepSeek-V4-ProGLM-4.5 vs DeepSeek-V4-ProGPT-4o mini vs Mistral Medium 3.5GLM-4.5 vs Mistral Medium 3.5