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