GPT Image 2.5 Dev vs GPT-6 Luna
| OpenAI GPT Image 2.5 Dev | OpenAI GPT-6 Luna | |
|---|---|---|
| Vendor | OpenAI | OpenAI |
| Context window | — | 1,050,000 |
| Max output | — | 128,000 |
| Reasoning | No | Yes |
| Tool calling | No | Yes |
| File input | Yes | Yes |
| Input | text, image | text, image |
| Output | image | text |
| Released | 2026-09-08 | 2026-09-22 |