GLM 5.3 vs GPT-5.1
| Z.ai GLM 5.3 | OpenAI GPT-5.1 | |
|---|---|---|
| Vendor | Z.ai | OpenAI |
| Context window | 1,000,000 | 400,000 |
| Max output | 128,000 | 128,000 |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| File input | No | Yes |
| Input | text | text, image |
| Output | text | text |
| Released | 2026-08-28 | 2025-11-12 |