grok-3 vs Claude Opus 5.5
| xAI grok-3 | Anthropic Claude Claude Opus 5.5 | |
|---|---|---|
| Vendor | xAI | Anthropic Claude |
| Context window | 131,072 | 1,000,000 |
| Max output | 8,192 | 128,000 |
| Reasoning | No | Yes |
| Tool calling | Yes | Yes |
| File input | Yes | Yes |
| Input | text | text, image, file |
| Output | text | text |
| Released | 2025-02-17 | 2026-09-22 |