As of October 21, 2026, Meta Muse Spark Open ranks #81 of 123 models overall with 44.9 ±17.7 on the LLMBenchmark Index. Muse Spark Open ranks #9 of 133 in web design, its strongest category. Meta Muse Spark Open costs $1.25 per million input tokens and $4.25 per million output tokens. Muse Spark Open was released on October 15, 2026.
Muse Spark Open's output price ranks 245 of 349 priced models, counting from the cheapest.
Listed on OpenRouter October 15, 2026, 6 days before our data. Results so far on 28 of 195 public boards; this page updates every day as boards publish.
Muse Spark Open is a coding-optimized open-weight model. Trained specifically for agentic coding workflows, it delivers higher first-attempt accuracy, reliable tool calling, and deep codebase understanding across the repos developers...
meta/muse-spark-open The tick on a coding bar is the median of every model measured on it. Outside coding, the place is this model's rank on that board. A board that never ran the model says so.
Measured in 4 of 7 categories. A place counts only the models measured on that board.
The index averages only the coding benchmarks that have a result; the others are skipped, never filled in. How it is weighted
Not measured on Aider polyglot, SWE-bench Verified, SWE-bench Lite, SWE-bench (full test set), SWE-bench Multimodal, SWE-bench Multilingual, AA Coding Index, LiveCodeBench (Vals AI), ProgramBench (Vals AI), IOI (Vals AI), Terminal-Bench 2.1 (Vals AI), SWE-bench Multimodal (Vals AI), Vibe Code Bench 1-100 (Vals AI), SkillsBench (Vals AI), CyberBench (Vals AI), LiveCodeBench (Artificial Analysis run), Terminal-Bench Hard (Artificial Analysis run), Terminal-Bench, DeepSWE, FrontierSWE, GSO-Bench, WeirdML, MirrorCode, Cybench, LMArena Text: coding, LMArena Text: software and IT, LMArena WebDev: from an image, SciCode
Not measured on AA Intelligence Index
Not measured on AA Agentic Index, Design Arena: agents building web apps, Design Arena: agents building full-stack apps, Design Arena: agents building mobile apps, Design Arena: agents building Android apps, Design Arena: agents building Godot games, Design Arena: agents building games, Design Arena: HTML slides, Design Arena: PowerPoint slides, Design Arena: spreadsheets, SREBench (Vals AI), BioMysteryBench (Vals AI), Terminal-Bench-Science (Vals AI), Vals Science Index, Time Horizon Index (Vals AI), CUA-bench (Vals AI), Robo-bench (Vals AI), τ²-Bench Telecom, METR time horizons, Remote Labor Index, GDPval, OSWorld 2.0, BALROG, DeepResearch Bench, PostTrainBench, TheAgentCompany, OSWorld, SpireClimb, Vending-Bench 2, LMArena Search, Berkeley Function Calling Leaderboard (BFCL), BrowseComp-Plus
Not measured on GPQA Diamond, MysteryMechanism (Vals AI), MMMU Pro (Vals AI), GPQA Diamond (Epoch AI run), ARC-AGI, ARC-AGI-2, Humanity's Last Exam, SimpleBench, Chess puzzles, Mystery game puzzles, EBR-bench, VPCT, BIG-Bench Hard, LMArena Text: hard prompts, LMArena Text: expert, LMArena Text: hard prompts in English, LMArena Vision: diagrams, LMArena Vision: homework, Kagi LLM Benchmark
Not measured on AIME, MATH 500 (Vals AI), MGSM (Vals AI), AA Math Index, AIME 2025 (Artificial Analysis run), OTIS Mock AIME, FrontierMath, tiers 1 to 3, FrontierMath, tier 4, ProofBench, MATH level 5, GSM8K, LMArena Text: math, LMArena Text: mathematical work
Not measured on MMLU Pro, LegalBench (Vals AI), CaseLaw (Vals AI), CorpFin (Vals AI), TaxEval (Vals AI), MortgageTax (Vals AI), MedQA (Vals AI), MedCode (Vals AI), MMLU Pro (Artificial Analysis run), SimpleQA Verified, MMLU, GeoBench, AI2 Reasoning Challenge, LMArena Text: science, LMArena Text: medicine and healthcare, LMArena Text: legal and government, LMArena Text: business and finance, FACTS Benchmark Suite
Not measured on Design Arena: UI components, Design Arena: data viz, Design Arena: 3D, Design Arena: all code categories, Design Arena: SVG, Design Arena: ASCII art
Not measured on Public Benefits Bench (Vals AI), SAGE (Vals AI), MedScribe (Vals AI), Vals Multimodal Index, IFBench, DTBench, LMCA, Fiction.LiveBench, Creative writing (Lech Mazur), CL-bench, Surface Evolver Bench, Furniture assembly, ExploitBench, HellaSwag, WinoGrande, PIQA, CL-bench Life, LMArena Text, LMArena Text: instruction following, LMArena Text: creative writing, LMArena Vision, LMArena Text: English, LMArena Text: non-English, LMArena Text: Chinese, LMArena Text: German, LMArena Text: Japanese, LMArena Text: Korean, LMArena Text: French, LMArena Text: Spanish, LMArena Text: Russian, LMArena Text: Polish, LMArena Text: multi-turn, LMArena Text: longer queries, LMArena Text: writing and language, LMArena Text: entertainment and media, LMArena Vision: English, LMArena Vision: Chinese, LMArena Vision: reading text, LMArena Vision: humor, LMArena Vision: captioning, LMArena Vision: recognizing things, LMArena Vision: creative writing, LMArena Document
Not measured on Design Arena: images, Design Arena: graphic design, Design Arena: logos, LMArena Text to Image, LMArena Image Edit
Public boards shown as published (Vals AI, Artificial Analysis, Design Arena) and kept out of the coding index. Each links to its source on the benchmark page.
| Benchmark | Result | Index weight |
|---|---|---|
| Aider polyglotCoding | Not measured | Not in index |
| SWE-bench VerifiedCoding | Not measured | Not in index |
| SWE-bench LiteCoding | Not measured | Not in index |
| SWE-bench (full test set)Coding | Not measured | Not in index |
| SWE-bench MultimodalCoding | Not measured | Not in index |
| SWE-bench MultilingualCoding | Not measured | Not in index |
| LiveBench codingCoding | 73.6% | 15% |
| LMArena WebDevCoding | 1528 | 10% |
| Vals IndexGeneral | 48.6% | Not in index |
| GPQA DiamondReasoning | Not measured | Not in index |
| AIMEMath | Not measured | Not in index |
| MMLU ProKnowledge | Not measured | Not in index |
| AA Intelligence IndexIntelligence | Not measured | Not in index |
| AA Coding IndexCoding | Not measured | Not in index |
| AA Agentic IndexAgentic work | Not measured | Not in index |
| Design Arena: websitesWeb design | 1317 | Not in index |
| Design Arena: UI componentsWeb design | Not measured | Not in index |
| Design Arena: game devWeb design | 1294 | Not in index |
| Design Arena: data vizWeb design | Not measured | Not in index |
| Design Arena: 3DWeb design | Not measured | Not in index |
| Design Arena: all code categoriesWeb design | Not measured | Not in index |
| Design Arena: SVGWeb design | Not measured | Not in index |
| Design Arena: ASCII artWeb design | Not measured | Not in index |
| Design Arena: agents building web appsAgentic work | Not measured | Not in index |
| Design Arena: agents building full-stack appsAgentic work | Not measured | Not in index |
| Design Arena: agents building mobile appsAgentic work | Not measured | Not in index |
| Design Arena: agents building Android appsAgentic work | Not measured | Not in index |
| Design Arena: agents building Godot gamesAgentic work | Not measured | Not in index |
| Design Arena: agents building gamesAgentic work | Not measured | Not in index |
| Design Arena: HTML slidesAgentic work | Not measured | Not in index |
| Design Arena: PowerPoint slidesAgentic work | Not measured | Not in index |
| Design Arena: spreadsheetsAgentic work | Not measured | Not in index |
| Design Arena: imagesImage generation | Not measured | Not in index |
| Design Arena: graphic designImage generation | Not measured | Not in index |
| Design Arena: logosImage generation | Not measured | Not in index |
| LiveBench reasoningReasoning | 73.7% | Not in index |
| LiveBench data analysisGeneral | 60.2% | Not in index |
| LiveBench researchAgentic work | 80.3% | Not in index |
| LiveBench browserAgentic work | 36.0% | Not in index |
| LiveBench long agenticAgentic work | 18.9% | Not in index |
| LiveBench designWeb design | 60.3% | Not in index |
| LiveCodeBench (Vals AI)Coding | Not measured | Not in index |
| SWE-bench Verified (Vals AI)Coding | Not measured | 15% |
| Terminal-Bench 4 (Vals AI)Coding | 6.6% | 25% |
| Vibe Code Bench (Vals AI)Coding | 76.2% | 20% |
| Code migration (Vals AI)Coding | 21.2% | Not in index |
| ProgramBench (Vals AI)Coding | Not measured | Not in index |
| SREBench (Vals AI)Agentic work | Not measured | Not in index |
| IOI (Vals AI)Coding | Not measured | Not in index |
| Terminal-Bench 2.1 (Vals AI)Coding | Not measured | Not in index |
| SWE-bench Multimodal (Vals AI)Coding | Not measured | Not in index |
| Vibe Code Bench 1-100 (Vals AI)Coding | Not measured | Not in index |
| SkillsBench (Vals AI)Coding | Not measured | Not in index |
| CyberBench (Vals AI)Coding | Not measured | Not in index |
| Finance Agent (Vals AI)Agentic work | 61.3% | Not in index |
| Tax Agent Bench (Vals AI)Agentic work | 26.3% | Not in index |
| Legal Research Bench (Vals AI)Agentic work | 38.5% | Not in index |
| Harvey's Legal Agent Benchmark (Vals AI)Agentic work | 25.0% | Not in index |
| Excel Modeling Benchmark (Vals AI)Agentic work | 53.7% | Not in index |
| BioMysteryBench (Vals AI)Agentic work | Not measured | Not in index |
| Terminal-Bench-Science (Vals AI)Agentic work | Not measured | Not in index |
| Vals Science IndexAgentic work | Not measured | Not in index |
| Time Horizon Index (Vals AI)Agentic work | Not measured | Not in index |
| CUA-bench (Vals AI)Agentic work | Not measured | Not in index |
| Robo-bench (Vals AI)Agentic work | Not measured | Not in index |
| Public Benefits Bench (Vals AI)General | Not measured | Not in index |
| MysteryMechanism (Vals AI)Reasoning | Not measured | Not in index |
| MMMU Pro (Vals AI)Reasoning | Not measured | Not in index |
| MATH 500 (Vals AI)Math | Not measured | Not in index |
| MGSM (Vals AI)Math | Not measured | Not in index |
| SAGE (Vals AI)General | Not measured | Not in index |
| LegalBench (Vals AI)Knowledge | Not measured | Not in index |
| CaseLaw (Vals AI)Knowledge | Not measured | Not in index |
| CorpFin (Vals AI)Knowledge | Not measured | Not in index |
| TaxEval (Vals AI)Knowledge | Not measured | Not in index |
| MortgageTax (Vals AI)Knowledge | Not measured | Not in index |
| MedQA (Vals AI)Knowledge | Not measured | Not in index |
| MedCode (Vals AI)Knowledge | Not measured | Not in index |
| MedScribe (Vals AI)General | Not measured | Not in index |
| Vals Multimodal IndexGeneral | Not measured | Not in index |
| AA Math IndexMath | Not measured | Not in index |
| GPQA Diamond (Artificial Analysis run)Reasoning | 89.0% | Not in index |
| Humanity's Last Exam (Artificial Analysis run)Reasoning | 43.9% | Not in index |
| MMLU Pro (Artificial Analysis run)Knowledge | Not measured | Not in index |
| LiveCodeBench (Artificial Analysis run)Coding | Not measured | Not in index |
| SciCodeCoding | 58.4% | Not in index |
| Terminal-Bench Hard (Artificial Analysis run)Coding | Not measured | Not in index |
| IFBenchGeneral | Not measured | Not in index |
| Long context reasoning (AA-LCR)General | 78.3% | Not in index |
| τ²-Bench TelecomAgentic work | Not measured | Not in index |
| AIME 2025 (Artificial Analysis run)Math | Not measured | Not in index |
| Terminal-BenchCoding | Not measured | Not in index |
| DeepSWECoding | Not measured | Not in index |
| FrontierCodeCoding | Not measured | 15% |
| FrontierSWECoding | Not measured | Not in index |
| GSO-BenchCoding | Not measured | Not in index |
| WeirdMLCoding | Not measured | Not in index |
| MirrorCodeCoding | Not measured | Not in index |
| APEX-AgentsAgentic work | 33.4% | Not in index |
| METR time horizonsAgentic work | Not measured | Not in index |
| Remote Labor IndexAgentic work | Not measured | Not in index |
| GDPvalAgentic work | Not measured | Not in index |
| OSWorld 2.0Agentic work | Not measured | Not in index |
| BALROGAgentic work | Not measured | Not in index |
| DeepResearch BenchAgentic work | Not measured | Not in index |
| PostTrainBenchAgentic work | Not measured | Not in index |
| GPQA Diamond (Epoch AI run)Reasoning | Not measured | Not in index |
| ARC-AGIReasoning | Not measured | Not in index |
| ARC-AGI-2Reasoning | Not measured | Not in index |
| Humanity's Last ExamReasoning | Not measured | Not in index |
| SimpleBenchReasoning | Not measured | Not in index |
| Chess puzzlesReasoning | Not measured | Not in index |
| Mystery game puzzlesReasoning | Not measured | Not in index |
| EBR-benchReasoning | Not measured | Not in index |
| OTIS Mock AIMEMath | Not measured | Not in index |
| FrontierMath, tiers 1 to 3Math | Not measured | Not in index |
| FrontierMath, tier 4Math | Not measured | Not in index |
| ProofBenchMath | Not measured | Not in index |
| MATH level 5Math | Not measured | Not in index |
| GSM8KMath | Not measured | Not in index |
| SimpleQA VerifiedKnowledge | Not measured | Not in index |
| MMLUKnowledge | Not measured | Not in index |
| GeoBenchKnowledge | Not measured | Not in index |
| DTBenchGeneral | Not measured | Not in index |
| LMCAGeneral | Not measured | Not in index |
| Fiction.LiveBenchGeneral | Not measured | Not in index |
| Creative writing (Lech Mazur)General | Not measured | Not in index |
| CL-benchGeneral | Not measured | Not in index |
| Surface Evolver BenchGeneral | Not measured | Not in index |
| Furniture assemblyGeneral | Not measured | Not in index |
| ExploitBenchGeneral | Not measured | Not in index |
| CybenchCoding | Not measured | Not in index |
| TheAgentCompanyAgentic work | Not measured | Not in index |
| OSWorldAgentic work | Not measured | Not in index |
| SpireClimbAgentic work | Not measured | Not in index |
| VPCTReasoning | Not measured | Not in index |
| BIG-Bench HardReasoning | Not measured | Not in index |
| AI2 Reasoning ChallengeKnowledge | Not measured | Not in index |
| HellaSwagGeneral | Not measured | Not in index |
| WinoGrandeGeneral | Not measured | Not in index |
| PIQAGeneral | Not measured | Not in index |
| CL-bench LifeGeneral | Not measured | Not in index |
| ALE-BenchCoding | 1590.1 | Not in index |
| Vending-Bench 2Agentic work | Not measured | Not in index |
| Epoch Capabilities IndexIntelligence | 155.1 | Not in index |
| LMArena TextGeneral | Not measured | Not in index |
| LMArena Text: codingCoding | Not measured | Not in index |
| LMArena Text: hard promptsReasoning | Not measured | Not in index |
| LMArena Text: mathMath | Not measured | Not in index |
| LMArena Text: instruction followingGeneral | Not measured | Not in index |
| LMArena Text: creative writingGeneral | Not measured | Not in index |
| LMArena VisionGeneral | Not measured | Not in index |
| LMArena Text: EnglishGeneral | Not measured | Not in index |
| LMArena Text: non-EnglishGeneral | Not measured | Not in index |
| LMArena Text: ChineseGeneral | Not measured | Not in index |
| LMArena Text: GermanGeneral | Not measured | Not in index |
| LMArena Text: JapaneseGeneral | Not measured | Not in index |
| LMArena Text: KoreanGeneral | Not measured | Not in index |
| LMArena Text: FrenchGeneral | Not measured | Not in index |
| LMArena Text: SpanishGeneral | Not measured | Not in index |
| LMArena Text: RussianGeneral | Not measured | Not in index |
| LMArena Text: PolishGeneral | Not measured | Not in index |
| LMArena Text: multi-turnGeneral | Not measured | Not in index |
| LMArena Text: longer queriesGeneral | Not measured | Not in index |
| LMArena Text: expertReasoning | Not measured | Not in index |
| LMArena Text: hard prompts in EnglishReasoning | Not measured | Not in index |
| LMArena Text: software and ITCoding | Not measured | Not in index |
| LMArena Text: mathematical workMath | Not measured | Not in index |
| LMArena Text: scienceKnowledge | Not measured | Not in index |
| LMArena Text: medicine and healthcareKnowledge | Not measured | Not in index |
| LMArena Text: legal and governmentKnowledge | Not measured | Not in index |
| LMArena Text: business and financeKnowledge | Not measured | Not in index |
| LMArena Text: writing and languageGeneral | Not measured | Not in index |
| LMArena Text: entertainment and mediaGeneral | Not measured | Not in index |
| LMArena WebDev: ReactCoding | 1529 | Not in index |
| LMArena WebDev: HTMLCoding | 1495 | Not in index |
| LMArena WebDev: from an imageCoding | Not measured | Not in index |
| LMArena Vision: EnglishGeneral | Not measured | Not in index |
| LMArena Vision: ChineseGeneral | Not measured | Not in index |
| LMArena Vision: reading textGeneral | Not measured | Not in index |
| LMArena Vision: diagramsReasoning | Not measured | Not in index |
| LMArena Vision: homeworkReasoning | Not measured | Not in index |
| LMArena Vision: humorGeneral | Not measured | Not in index |
| LMArena Vision: captioningGeneral | Not measured | Not in index |
| LMArena Vision: recognizing thingsGeneral | Not measured | Not in index |
| LMArena Vision: creative writingGeneral | Not measured | Not in index |
| LMArena SearchAgentic work | Not measured | Not in index |
| LMArena DocumentGeneral | Not measured | Not in index |
| LMArena Text to ImageImage generation | Not measured | Not in index |
| LMArena Image EditImage generation | Not measured | Not in index |
| Berkeley Function Calling Leaderboard (BFCL)Agentic work | Not measured | Not in index |
| Kagi LLM BenchmarkReasoning | Not measured | Not in index |
| BrowseComp-PlusAgentic work | Not measured | Not in index |
| SciCodeCoding | Not measured | Not in index |
| FACTS Benchmark SuiteKnowledge | Not measured | Not in index |
A list price says what a token costs. The cost per solved task says what a working answer costs, which is the number that decides.
Neither board that publishes what a SWE-bench Verified attempt costs, Vals AI and swebench.com, has run this model. We leave the number out rather than estimate it.
LiveBench, on its own coding tasks, publishes what one task cost this model: $1.253, at a score of 73.6%. LiveBench counts that as $1.702 per successful task. Different tasks from SWE-bench, so it is not our number and does not enter its ranking. LiveBench coding
Beside a result, many boards publish what the run cost, how long it took, the tokens it spent or the votes behind a rating. Each figure as its board printed it, one board per row.
| Board | Result | What the run cost | Also published |
|---|---|---|---|
| LiveBench coding | 73.6% | $1.2525 per task | Output tokens per task 26,529 |
| Vals Index | 48.6% | $4.72 per test | Duration, as printed 1h 22m |
| LiveBench reasoning | 73.7% | $0.0427 per task | Output tokens per task 9,861 |
| LiveBench data analysis | 60.2% | $0.0449 per task | Output tokens per task 9,999 |
| LiveBench research | 80.3% | $0.732 per task | Output tokens per task 22,757 |
| LiveBench browser | 36.0% | $2.6434 per task | Output tokens per task 23,505 |
| LiveBench long agentic | 18.9% | $4.8336 per task | Output tokens per task 133,814 |
| LiveBench design | 60.3% | $0.3559 per task | Output tokens per task 32,098 |
| Terminal-Bench 4 (Vals AI) | 6.6% | $7.26 per test | Duration, as printed 2h 04m |
| Vibe Code Bench (Vals AI) | 76.2% | $1.66 per test | Duration, as printed 31m 09s |
| Code migration (Vals AI) | 21.2% | $9.04 per test | Duration, as printed 1h 53m |
| Finance Agent (Vals AI) | 61.3% | $0.77 per test | Duration, as printed 24m 13s |
| Tax Agent Bench (Vals AI) | 26.3% | $0.88 per test | Duration, as printed 11m 42s |
|---|---|---|---|
| Legal Research Bench (Vals AI) | 38.5% | $1.56 per test | Duration, as printed 29m 23s |
| Harvey's Legal Agent Benchmark (Vals AI) | 25.0% | $13.63 per test | Duration, as printed 3h 59m |
| Excel Modeling Benchmark (Vals AI) | 53.7% | $5.35 per test | Duration, as printed 1h 25m |
| ALE-Bench | 1590.1 | $0.3255 per problem | Tokens per problem 99,073 |
| LMArena WebDev | 1528 Elo | Not published | Votes 1,380 · Interval (±) ±17.0 |
| Design Arena: websites | 1317 Elo | Not published | Battles 308 |
| Design Arena: game dev | 1294 Elo | Not published | Battles 241 |
| APEX-Agents | 33.4% | Not published | Mean score 48.7% |
| LMArena WebDev: React | 1529 Elo | Not published | Votes 864 · Interval (±) ±21.9 |
| LMArena WebDev: HTML | 1495 Elo | Not published | Votes 173 · Interval (±) ±48.6 |