o3-mini vs Claude Opus 5.5
| OpenAI o3-mini | Anthropic Claude Claude Opus 5.5 | |
|---|---|---|
| Vendor | OpenAI | Anthropic Claude |
| Context window | 200,000 | 1,000,000 |
| Max output | 100,000 | 128,000 |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| File input | No | Yes |
| Input | text | text, image, file |
| Output | text | text |
| Released | 2024-12-20 | 2026-09-22 |