In short
How they differ.
Worked out from the figures below. Prices and specs are the makers' own, read Oct 20, 2026.
- Muse Wonder reads more at once: a context window of 1M tokens against 1M.
- Muse Spark Open can be downloaded and run on your own machine; Muse Wonder can't.
- On the 2 independent boards that rank both, Muse Wonder places higher on 2 and Muse Spark Open on 0.
Side by side
The specs.
| Muse Spark Open | Muse Wonder | |
|---|---|---|
| Made by | Meta · US | Meta · US |
| Released | Oct 15, 2026 | Oct 12, 2026 |
| Price per 1M tokens | Free to download; hosts set prices | $4 in / $20 out |
| Context window | 1M | 1M |
| Takes in | text, image, video, audio | text, image, video, audio, pdf |
| Download and run it yourself | Yes (Muse Model License) | No |
| Size | 816B parameters, 42B active | Not published |
| Maker says | “The most capable US open-weight model to date. Build your way, anywhere.” | “Frontier coding, long-running agents, and advanced computer use.” |
| 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.
| Board | Muse Spark Open | Muse Wonder |
|---|---|---|
| LMArena textLMArena, Oct 15, 2026 | Not listed | #2 |
| LMArena creative writingLMArena, Oct 15, 2026 | Not listed | #8 |
| LMArena coding chatsLMArena, Oct 15, 2026 | Not listed | #5 |
| LMArena WebDevLMArena, Oct 19, 2026 | Not listed | #17 |
| LMArena Agent ArenaLMArena, Oct 19, 2026 | Not listed | #13 |
| Humanity's Last ExamScale AI | #11 | #7 |
| SWE-Bench ProScale AI, Sep 22, 2026 | #11 | #6 |
More comparisons