Claude Opus 5 vs GPT-6 Luna
| Anthropic Claude Claude Opus 5 | OpenAI GPT-6 Luna | |
|---|---|---|
| Vendor | Anthropic Claude | OpenAI |
| Context window | 1,000,000 | 1,050,000 |
| Max output | 128,000 | 128,000 |
| Reasoning | Yes | Yes |
| Tool calling | Yes | Yes |
| File input | Yes | Yes |
| Input | text, image, file | text, image |
| Output | text | text |
| Released | 2026-07-24 | 2026-09-22 |