GPT-5.5 vs o4-mini
| OpenAI GPT-5.5 | OpenAI o4-mini | |
|---|---|---|
| Vendor | OpenAI | OpenAI |
| Context window | 1,050,000 | 200,000 |
| Max output | 128,000 | 100,000 |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| File input | Yes | Yes |
| Input | text, image | text, image |
| Output | text | text |
| Released | 2026-04-23 | 2025-04-16 |