GPT-5.5 vs Muse Spark
GPT-5.5 
Muse Spark Verdict
- GPT-5.5 leads on quality: 66.6 vs 65.4.
- GPT-5.5 is stronger in agents & tools, composite, knowledge, long context.
- Muse Spark is stronger in coding, human preference, instruction following, multimodal, reasoning, maths.
| Metric | GPT-5.5 | Muse Spark |
|---|---|---|
| BenchLeader Index | 66.6 | 65.4 |
| Agents & tools score | 68.4 | 66.3 |
| Coding score | 57.3 | 66.0 |
| Composite score | 77.7 | 68.4 |
| Human preference score | 67.6 | 69.0 |
| Instruction following score | 73.3 | 79.6 |
| Knowledge score | 73.7 | 64.5 |
| Long context score | 68.8 | 65.5 |
| Multimodal score | 64.9 | 65.9 |
| Reasoning score | 69.7 | 70.0 |
| Maths score | – | 56.3 |
| Blended price $/M | $11.25 | – |
| Output speed | 88 tok/s | – |
| Time to first answer | 62.3 s | – |
| Context window | 1.1M | 262k |
| GPQA Diamond | – | 89.8% |
| OTIS Mock AIME | – | 88.9% |
| Humanity's Last Exam | – | 40.6% |
| Terminal-Bench | 84.7% | – |
| SimpleBench | 69.0% | – |
| SciCode | – | 51.5% |
| Remote Labor Index | 6.3% | – |
| APEX-Agents | 38.5% | – |
| FrontierCode | 43.0% | – |
| ProofBench | – | 17.0% |
| Epoch Capabilities Index | 159.1 | 152.1 |
| LMArena Text | 1477 | 1488 |
| LMArena Hard Prompts | 1498 | 1505 |
| LMArena Coding | 1509 | 1526 |
| LMArena WebDev | 1458 | – |
| LMArena Vision | 1296 | 1306 |
| LMArena Agent | 3 | – |
| AA Intelligence Index | 38.6 | 31.3 |
| IFBench | 75.8% | 75.9% |
| AA-LCR | 84.3% | 78.0% |
| MMMU-Pro | 79.9% | 80.5% |
| AA-Omniscience | 20.5 | 7.2 |
| Terminal-Bench Hard | 60.6% | 45.5% |
| GPQA Diamond (AA) | 93.5% | 88.4% |
| Humanity's Last Exam (AA) | 45.8% | 40.7% |
| SciCode (AA) | 55.8% | – |
| τ²-Bench Telecom (AA) | 93.9% | 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% |
| HiL-Bench | 39.7% | – |
| TutorBench | – | 68.5% |
| EQ-Bench 4 | 1315 | – |
| Kagi LLM Benchmark | 88.8% | – |
Data as of 2026-09-09. Best configuration of each model; every score links to its source on the model pages.