Muse Spark
Made by Meta, released 8 Apr 2026. Epoch AI lists its access as “API access”. Appears solid at writing among the models listed here.
In short
What it does well
- Writing: Strong (22nd of 77 listed models)
Where it falls short
- Coding: Middle (43rd of 77 listed models)
What we don't know yet
- Web-building votes: Not enough data
- Hard maths problems: Not enough data
- Short factual questions: Not enough data
- Fixing real software bugs: Not enough data
- Difficult coding tasks: Not enough data
The four ratings
- Top tier
- Strong
- Middle
- Behind the leaders
- Not enough data
Ratings compare only the 77 models listed here, in quarters, best first. “Not enough data” means no result yet. It is never a low score.
- Writing
- StrongHow often people preferred its answers to writing prompts. 1,459 on Arena's scale · Source for Muse Spark writing score (lmarena)
- Coding
- MiddleHow often people preferred its answers to coding questions. 1,481 on Arena's scale · Source for Muse Spark coding score (lmarena)
- Maths
- Not enough dataNo result yet for hard maths problems.
- Knowledge
- Not enough dataNo result yet for short factual questions.
Evidence completeness: Partial evidence, 8 of 13 tests have a result.
Where it is relatively stronger or weaker
This compares each kind of request with the model's own overall position among the 77 listed models, using Arena's votes. It is about performance on different languages, kinds of request and topics, not about political or social bias.
Relatively stronger
No category stands out as clearly stronger than its overall position.
Relatively weaker
- Expert-level prompts: 57th of 77 on prompts that need expert knowledge, against 22nd of 77 overall. Source for Expert-level prompts
- Long prompts: 50th of 77 on long, detailed prompts, against 22nd of 77 overall. Source for Long prompts
Show every category we can see
| Category | Position | Arena score | Votes | Source |
|---|---|---|---|---|
| Expert-level prompts Kind of request | 57th of 77 | 1,457 95% range 1,441 to 1,473 | 1,377 | Source for Expert-level prompts |
| Hard prompts Kind of request | 36th of 77 | 1,474 95% range 1,467 to 1,481 | 9,155 | Source for Hard prompts |
| Long prompts Kind of request | 50th of 77 | 1,450 95% range 1,442 to 1,459 | 5,602 | Source for Long prompts |
| Longer conversations Kind of request | 23rd of 77 | 1,477 95% range 1,464 to 1,490 | 2,282 | Source for Longer conversations |
| Chinese Language | 36th of 76 | 1,507 95% range 1,488 to 1,527 | 976 | Source for Chinese |
| English prompts Language | 20th of 77 | 1,480 95% range 1,473 to 1,488 | 6,679 | Source for English prompts |
| French Language | 15th of 72 | 1,496 95% range 1,468 to 1,524 | 478 | Source for French |
| Non-English prompts Language | 26th of 77 | 1,463 95% range 1,456 to 1,471 | 7,461 | Source for Non-English prompts |
| Russian Language | 32nd of 77 | 1,466 95% range 1,451 to 1,481 | 1,574 | Source for Russian |
| Spanish Language | 24th of 70 | 1,470 95% range 1,444 to 1,496 | 519 | Source for Spanish |
| Entertainment, sport and media Topic | 23rd of 77 | 1,449 95% range 1,437 to 1,461 | 2,634 | Source for Entertainment, sport and media |
| Law and government Topic | 23rd of 76 | 1,484 95% range 1,465 to 1,503 | 1,019 | Source for Law and government |
| Medicine and health Topic | 27th of 75 | 1,475 95% range 1,456 to 1,495 | 994 | Source for Medicine and health |
| Science Topic | 34th of 77 | 1,475 95% range 1,463 to 1,488 | 2,372 | Source for Science |
| Software and IT Topic | 32nd of 77 | 1,487 95% range 1,479 to 1,495 | 5,551 | Source for Software and IT |
Bias: what we can and can't see
Our sources do not measure political lean, stereotyping, flattery (agreeing with you too readily) or safety behaviour, so we cannot say how any model does on those. What we can show is above: where a model is relatively stronger or weaker across languages, kinds of request and topics. Also, people voting in Arena can favour answer style, such as length and formatting, and our numbers do not adjust for that. See what AI bias means and what these tests can tell you.
Best-supported use cases
- Coding and building things: not ranked, because there is not enough data for the main test.
- Homework and maths: not ranked, because there is not enough data for the main test.
- Research and checking facts: not ranked, because there is not enough data for the main test.
Where an alternative might be more suitable
- Writing and creating content: rated Strong on writing votes. Compare it with Claude Opus 5.5, the best-supported choice for this task.
- Coding and building things: rated Middle on coding votes. Compare it with Claude Opus 5.5, the best-supported choice for this task.
- Homework and maths: no result on hard maths problems, so we cannot say. See which models the evidence does support.
- Business emails and everyday work: rated Strong on business-task votes. Compare it with Gemini 4 Argon, the best-supported choice for this task.
- Research and checking facts: no result on short factual questions, so we cannot say. See which models the evidence does support.
What it is
- Maker
- Meta
- Release date (Epoch AI)
- 8 Apr 2026
- Access, as listed by Epoch AI
- API access
- Licence, as listed by Arena
- Proprietary
- Maker's country (Epoch AI)
- United States of America
- Last observation in our data
- 28 Oct 2026
- Data last changed
- 29 Oct 2026, 14:36 UTC
We have not verified an official product page for this model, so we do not link to one.
How you can use it
Proprietary. The model's files are not published, so it is generally available only through its maker or partners the maker chooses.
How you can reach it (an app, a website, a developer API or a third-party tool) and what that costs are not covered by our benchmark data. Where we could verify prices from the maker's own pages, they are shown under Price. Epoch AI lists access as “API access”. See models, apps and harnesses and how AI pricing works.
Price
Price not independently verified
We have not been able to check this maker's own pricing page, so we show nothing for it.
We never infer subscription prices from API prices. New to “tokens” and “per million”? See how AI pricing works.
Good to remember
- Benchmarks are samples of tasks. None proves performance in every situation.
- Arena scores come from people choosing between answers. That measures preference, not correctness.
- Ratings are relative to the 77 models listed here. A different set would change them.
- Sources test models at different settings. Each result shows the setting used, and we do not adjust it.
The evidence, for the curious
Show all 13 tests with settings and sources
| Test | Result | Rating | Setting used | Source identifier | Observed | Links |
|---|---|---|---|---|---|---|
| Arena text: overall preference Arena 'text' leaderboard (Bradley-Terry rating, no style control) |
1,474 Arena score 95% range 1,468 to 1,480, 14,140 votes |
Strong | effort: not stated, bradley-terry rating | Muse Spark lmarena · text/latest |
28 Oct 2026 | Source for Muse Spark Arena text: overall preference score (lmarena) |
| Arena text: creative writing Arena 'text' leaderboard, category creative_writing |
1,459 Arena score 95% range 1,445 to 1,472, 2,038 votes |
Strong | effort: not stated, bradley-terry rating | Muse Spark lmarena · text/latest |
28 Oct 2026 | Source for Muse Spark Arena text: creative writing score (lmarena) |
| Arena text: coding Arena 'text' leaderboard, category coding |
1,481 Arena score 95% range 1,471 to 1,491, 3,941 votes |
Middle | effort: not stated, bradley-terry rating | Muse Spark lmarena · text/latest |
28 Oct 2026 | Source for Muse Spark Arena text: coding score (lmarena) |
| Arena text: maths Arena 'text' leaderboard, category math |
1,456 Arena score 95% range 1,436 to 1,475, 892 votes |
Middle | effort: not stated, bradley-terry rating | Muse Spark lmarena · text/latest |
28 Oct 2026 | Source for Muse Spark Arena text: maths score (lmarena) |
| Arena text: following instructions Arena 'text' leaderboard, category instruction_following |
1,442 Arena score 95% range 1,433 to 1,451, 4,739 votes |
Middle | effort: not stated, bradley-terry rating | Muse Spark lmarena · text/latest |
28 Oct 2026 | Source for Muse Spark Arena text: following instructions score (lmarena) |
| Arena text: business and management Arena 'text' leaderboard, category industry_business_and_management_and_financial_operations |
1,462 Arena score 95% range 1,451 to 1,473, 2,863 votes |
Strong | effort: not stated, bradley-terry rating | Muse Spark lmarena · text/latest |
28 Oct 2026 | Source for Muse Spark Arena text: business and management score (lmarena) |
| Arena WebDev: building web apps | Not enough data | |||||
| FrontierMath Tiers 1-3 (v2) | Not enough data | |||||
| OTIS Mock AIME 2024-2025 OTIS Mock AIME 2024-2025, benchmark released 2024-12-19 |
88.9% share of problems solved standard error ±4.7 points |
Behind the leaders | effort: not stated, best score across scorers | muse-spark epoch · otis_mock_aime_2024_2025.csv |
8 Apr 2026 | Source for Muse Spark OTIS Mock AIME 2024-2025 score (epoch) No public run log in the data file. |
| GPQA Diamond GPQA Diamond, benchmark released 2023-11-20 |
89.8% share of questions correct standard error ±2.2 points |
Middle | effort: not stated, best score across scorers | muse-spark epoch · gpqa_diamond.csv |
8 Apr 2026 | Source for Muse Spark GPQA Diamond score (epoch) No public run log in the data file. |
| SimpleQA Verified | Not enough data | |||||
| SWE-bench Verified (Epoch runs) | Not enough data | |||||
| FrontierCode (reported by Cognition) | Not enough data | |||||
Missing evidence
Not enough data for these tests:
- Arena WebDev: building web apps
- FrontierMath Tiers 1-3 (v2)
- SimpleQA Verified
- SWE-bench Verified (Epoch runs)
- FrontierCode (reported by Cognition)
Missing results are not low scores and do not count against the model.
Where a source gives no public run log, we cannot show the run behind the score. See data sources.
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