gpt-5-pro vs GLM 5.3 Flash
| OpenAI gpt-5-pro | Z.ai GLM 5.3 Flash | |
|---|---|---|
| Vendor | OpenAI | Z.ai |
| Context window | 400,000 | 1,000,000 |
| Max output | 272,000 | 128,000 |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| File input | Yes | No |
| Input | text, image | text |
| Output | text | text |
| Released | 2025-08-07 | 2026-08-25 |