GLM 5.3 Flash vs GPT Image 2.5 Dev
| Z.ai GLM 5.3 Flash | OpenAI GPT Image 2.5 Dev | |
|---|---|---|
| Vendor | Z.ai | OpenAI |
| Context window | 1,000,000 | — |
| Max output | 128,000 | — |
| Reasoning | Yes | No |
| Tool calling | Yes | No |
| File input | No | Yes |
| Input | text | text, image |
| Output | text | image |
| Released | 2026-08-25 | 2026-09-08 |