GPT-5.5 Pro vs Muse Spark 1.2
GPT-5.5 Pro 
Muse Spark 1.2 Verdict
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 64.1.
- GPT-5.5 Pro (xhigh) is stronger in maths, reasoning.
- Muse Spark 1.2 (xhigh) is stronger in agents & tools, coding, composite, human preference, knowledge, long context, multimodal.
- Muse Spark 1.2 (xhigh) is 34× cheaper ($2.00 vs $67.50 per 1M blended).
- Muse Spark 1.2 (xhigh) streams 51.8× faster (207 vs 4 tokens per second).
| Metric | GPT-5.5 Pro (xhigh) | Muse Spark 1.2 (xhigh) |
|---|---|---|
| BenchLeader Index | 67.1 | 64.1 |
| Maths score | 74.5 | – |
| Reasoning score | 80.1 | 73.8 |
| Agents & tools score | – | 57.5 |
| Coding score | – | 57.2 |
| Composite score | – | 69.9 |
| Human preference score | – | 70.6 |
| Knowledge score | – | 67.9 |
| Long context score | – | 65.9 |
| Multimodal score | – | 66.0 |
| Blended price $/M | $67.50 | $2.00 |
| Output speed | 4 tok/s | 207 tok/s |
| Time to first answer | 3.5 s | 22.3 s |
| Context window | 1.1M | 1.0M |
| FrontierMath Tiers 1–3 | 87.7% | – |
| FrontierMath Tier 4 | 78.0% | – |
| 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 | – | 39.8 |
| AA-LCR | – | 79.0% |
| AA-Omniscience | – | 27.2 |
| GPQA Diamond (AA) | – | 90.4% |
| Humanity's Last Exam (AA) | – | 45.5% |
| SciCode (AA) | – | 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 |
| ARC-AGI-1 | 95.0% | – |
| ARC-AGI-2 | 84.2% | – |
| CritPt | 30.6% | 17.7% |
| GDPval (AA) | – | 51.2% |
| 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 | 53.9% | 48.4% |
| DTBench | 96.0% | 94.7% |
| GDP.pdf | – | 16.0% |
| FrontierSWE | – | 12.0% |
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 1.2: questions
- Is GPT-5.5 Pro better than Muse Spark 1.2?
- GPT-5.5 Pro (xhigh) leads on quality: 67.1 vs 64.1. 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 is cheaper, GPT-5.5 Pro or Muse Spark 1.2?
- Muse Spark 1.2 is cheaper: $2.00 against $67.50 per million tokens, blended at three input tokens per output token.
- Which is faster, GPT-5.5 Pro or Muse Spark 1.2?
- Muse Spark 1.2 streams faster: 207 against 4 output tokens per second.
- Which has the larger context window?
- GPT-5.5 Pro accepts more context: 1.1M against 1.0M tokens.