In short
How they differ.
Worked out from the figures below. Prices and specs are the makers' own, read Oct 20, 2026.
- No independent board we follow ranks both models yet.
Side by side
The specs.
| Claude Mythos 5.1 | GPT-6 Luna | |
|---|---|---|
| Made by | Anthropic · US | OpenAI · US |
| Released | Sep 1, 2026 | Sep 22, 2026 |
| Price per 1M tokens | No public price | $0.10 in / $0.50 out |
| Context window | Not stated | 1M |
| Takes in | Not stated | text, image |
| Download and run it yourself | No | No |
| Size | Not published | Not published |
| Maker says | “Our most capable model for cybersecurity and biology research.” | “Our most efficient model for focused, high-volume tasks.” |
| Sources | Prices, Oct 20, 2026 · Description | Prices, Oct 20, 2026 · Description |
Independent tests
Where they place.
Position on each board we follow (1 is best). Epoch AI's and Vectara's scores are shown; the other boards are linked for their own figures.
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