GPT-5.5 Pro vs Muse Spark
GPT-5.5 Pro 
Muse Spark Verdict
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 65.7.
- GPT-5.5 Pro (xhigh) is stronger in maths, reasoning.
- Muse Spark is stronger in agents & tools, coding, composite, human preference, instruction following, knowledge, long context, multimodal.
| Metric | GPT-5.5 Pro (xhigh) | Muse Spark |
|---|---|---|
| BenchLeader Index | 67.1 | 65.7 |
| Maths score | 74.5 | 59.9 |
| Reasoning score | 80.1 | 68.3 |
| Agents & tools score | – | 66.0 |
| Coding score | – | 66.1 |
| Composite score | – | 68.7 |
| Human preference score | – | 69.2 |
| Instruction following score | – | 79.8 |
| Knowledge score | – | 64.2 |
| Long context score | – | 65.4 |
| Multimodal score | – | 65.7 |
| Blended price $/M | $67.50 | – |
| Output speed | 4 tok/s | – |
| Time to first answer | 3.5 s | – |
| Context window | 1.1M | 262k |
| GPQA Diamond | – | 89.8% |
| FrontierMath Tiers 1–3 | 87.7% | – |
| FrontierMath Tier 4 | 78.0% | – |
| OTIS Mock AIME | – | 88.9% |
| Humanity's Last Exam | – | 40.6% |
| SciCode | – | 51.5% |
| ProofBench | – | 17.0% |
| Epoch Capabilities Index | – | 152.1 |
| LMArena Text | – | 1488 |
| LMArena Hard Prompts | – | 1505 |
| LMArena Coding | – | 1526 |
| LMArena Vision | – | 1306 |
| AA Intelligence Index | – | 31.3 |
| IFBench | – | 75.9% |
| AA-LCR | – | 78.0% |
| MMMU-Pro | – | 80.5% |
| AA-Omniscience | – | 7.2 |
| Terminal-Bench Hard | – | 45.5% |
| GPQA Diamond (AA) | – | 88.4% |
| Humanity's Last Exam (AA) | – | 40.7% |
| τ²-Bench Telecom (AA) | – | 91.5% |
| AIME (Vals) | – | 96.9% |
| MMLU-Pro | – | 87.3% |
| LegalBench | – | 84.2% |
| CorpFin | – | 65.1% |
| TaxEval | – | 77.7% |
| SWE-bench (Vals) | – | 74.4% |
| GPQA Diamond (Vals) | – | 89.7% |
| SWE-Bench Pro | – | 55.0% |
| MCP Atlas | – | 82.2% |
| MultiChallenge | – | 75.5% |
| PRBench Finance | – | 52.4% |
| PRBench Legal | – | 52.3% |
| MultiNRC | – | 59.0% |
| TutorBench | – | 68.5% |
| ARC-AGI-1 | 95.0% | – |
| ARC-AGI-2 | 84.2% | – |
| CritPt | 30.6% | 11.3% |
| GDPval (AA) | – | 28.8% |
| CaseLaw v2 | – | 63.1% |
| MedCode | – | 51.3% |
| MedScribe | – | 85.9% |
| MMMU-Pro (Vals) | – | 87.4% |
| Terminal-Bench 2.0 (Vals) | – | 59.5% |
| Vibe Code Bench v1.1 | – | 19.7% |
| FORTRESS | – | 20.2% |
| SWE-Bench Pro (private) | – | 44.7% |
| SWE Atlas: Codebase QnA | – | 24.2% |
| SWE Atlas: Test Writing | – | 31.1% |
| LMArena Maths | – | 1461 |
| LMArena Creative Writing | – | 1464 |
| LMArena Instruction Following | – | 1463 |
| LMArena Multi-turn | – | 1491 |
| LMArena Longer Queries | – | 1474 |
| LMArena Document | – | 1467 |
| LMCA | 53.9% | – |
| DTBench | 96.0% | – |
Data as of 2026-09-19. Best configuration of each model; every score links to its source on the model pages.
GPT-5.5 Pro vs Muse Spark: questions
- Is GPT-5.5 Pro better than Muse Spark?
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 65.7. The BenchLeader Index combines every independent quality benchmark; GPT-5.5 Pro (xhigh) is ahead overall as of 2026-09-19, but check the category scores for your use.
- Which has the larger context window?
- GPT-5.5 Pro accepts more context: 1.1M against 262k tokens.