Claude Opus 5.5 vs Muse Spark 1.2
Claude Opus 5.5 
Muse Spark 1.2 Verdict
- Claude Opus 5.5 (thinking) leads on quality: 70.7 vs 63.7.
- Claude Opus 5.5 (thinking) is stronger in composite, knowledge, long context, multimodal, reasoning.
- Muse Spark 1.2 (xhigh) is stronger in agents & tools, coding, human preference.
- Muse Spark 1.2 (xhigh) is 4.0× cheaper ($2.00 vs $8.00 per 1M blended).
- Muse Spark 1.2 (xhigh) streams 3.6× faster (174 vs 48 tokens per second).
| Metric | Claude Opus 5.5 (thinking) | Muse Spark 1.2 (xhigh) |
|---|---|---|
| BenchLeader Index | 70.7 | 63.7 |
| Composite score | 95.0 | 68.8 |
| Knowledge score | 85.0 | 67.6 |
| Long context score | 68.5 | 65.6 |
| Multimodal score | 71.9 | 66.0 |
| Reasoning score | 95.0 | 72.5 |
| Agents & tools score | – | 57.5 |
| Coding score | – | 56.9 |
| Human preference score | – | 70.6 |
| Blended price $/M | $8.00 | $2.00 |
| Output speed | 48 tok/s | 174 tok/s |
| Time to first answer | 4.2 s | 28.9 s |
| Context window | 1M | 1.0M |
| SimpleQA Verified | – | 60.3% |
| SciCode | – | 56.4% |
| WeirdML | – | 60.3% |
| LMArena Text | – | 1500 |
| LMArena Hard Prompts | – | 1513 |
| LMArena Coding | – | 1536 |
| LMArena WebDev | – | 1534 |
| LMArena Vision | – | 1304 |
| LMArena Agent | – | -1.8 |
| LiveBench | – | 78.0% |
| LiveBench Reasoning | – | 90.0% |
| LiveBench Coding | – | 77.5% |
| LiveBench Agentic Coding | – | 57.6% |
| LiveBench Mathematics | – | 91.2% |
| LiveBench Data Analysis | – | 76.5% |
| LiveBench Language | – | 78.6% |
| LiveBench Instruction Following | – | 74.3% |
| AA Intelligence Index | 57.6 | 39.6 |
| AA-LCR | 84.7% | 79.0% |
| MMMU-Pro | 87.7% | – |
| AA-Omniscience | 46.4 | 27.2 |
| GPQA Diamond (AA) | – | 90.4% |
| Humanity's Last Exam (AA) | 61.4% | 45.5% |
| SciCode (AA) | 66.9% | 57.4% |
| MMLU-Pro | – | 88.3% |
| IOI | – | 21.8% |
| LegalBench | – | 85.3% |
| CorpFin | – | 70.9% |
| TaxEval | – | 80.4% |
| Terminal-Bench 2.1 (Vals) | – | 69.7% |
| SWE-bench (Vals) | – | 86.6% |
| Vals Index | – | 57.0 |
| CritPt | 31.7% | 17.7% |
| GDPval (AA) | 67.3% | 49.1% |
| τ²-Bench Banking (AA) | – | 34.9% |
| BioMysteryBench | – | 64.8% |
| Code Migration | – | 29.9% |
| Excel Modeling Benchmark | – | 57.0% |
| Finance Agent v2 | – | 60.6% |
| Harvey's Legal Agent Benchmark | – | 25.4% |
| Legal Research Bench | – | 43.8% |
| MedCode | – | 49.4% |
| MedScribe | – | 90.1% |
| MMMU-Pro (Vals) | – | 86.1% |
| MortgageTax | – | 65.4% |
| Public Benefits Bench | – | 68.5% |
| SAGE | – | 47.7% |
| SkillsBench | – | 53.0% |
| Terminal-Bench 4.0 (Vals) | – | 5.6% |
| Vibe Code Bench v1.1 | – | 79.1% |
| LMArena Creative Writing | – | 1452 |
| LMArena Instruction Following | – | 1480 |
| LMArena Multi-turn | – | 1520 |
| LMArena Longer Queries | – | 1502 |
| DeepSWE | – | 54.9% |
| LMCA | – | 48.4% |
| DTBench | – | 94.7% |
| GDP.pdf | – | 16.0% |
| FrontierSWE | – | 12.0% |
| Terminal-Bench 4.0 (AA) | 59.6% | 7.1% |
| Terminal-Bench 2.1 (AA) | – | 80.2% |
| AutomationBench | 69.5% | 40.6% |
| GDP.pdf | 26.2% | 17.4% |
| MLCR | – | 31.1% |
| Harvey LAB | 91.2% | – |
| EnterpriseOps-Gym | – | 47.3% |
| AA-Omniscience: accuracy | 66.2% | 45.4% |
| AA-Omniscience: non-hallucination | 41.4% | 66.7% |
| AA-Briefcase | 1822 | 1340 |
Data as of 2026-09-22. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 5.5 vs Muse Spark 1.2: questions
- Is Claude Opus 5.5 better than Muse Spark 1.2?
- Claude Opus 5.5 (thinking) leads on quality: 70.7 vs 63.7. The BenchLeader Index combines every independent quality benchmark; Claude Opus 5.5 (thinking) is ahead overall as of 2026-09-22, but check the category scores for your use.
- Which is cheaper, Claude Opus 5.5 or Muse Spark 1.2?
- Muse Spark 1.2 is cheaper: $2.00 against $8.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 5.5 or Muse Spark 1.2?
- Muse Spark 1.2 streams faster: 174 against 48 output tokens per second.
- Which has the larger context window?
- Muse Spark 1.2 accepts more context: 1.0M against 1M tokens.