Grok 4.20 vs Muse Spark 1.3
Grok 4.20 
Muse Spark 1.3 Verdict
- Muse Spark 1.3 (max) leads on quality: 69.3 vs 59.9.
- Grok 4.20 (thinking) is stronger in instruction following.
- Muse Spark 1.3 (max) is stronger in agents & tools, coding, composite, human preference, knowledge, long context, maths, multimodal, reasoning.
- Grok 4.20 (thinking) is 1.3× cheaper ($1.56 vs $2.00 per 1M blended).
- Muse Spark 1.3 (max) streams 2.2× faster (223 vs 101 tokens per second).
| Metric | Grok 4.20 (thinking) | Muse Spark 1.3 (max) |
|---|---|---|
| BenchLeader Index | 59.9 | 69.3 |
| Agents & tools score | 51.7 | 71.1 |
| Coding score | 54.7 | 66.6 |
| Composite score | 61.5 | 90.1 |
| Human preference score | 67.1 | 69.8 |
| Instruction following score | 79.9 | – |
| Knowledge score | 56.8 | 76.1 |
| Long context score | 60.7 | 68.0 |
| Maths score | 55.6 | 69.2 |
| Multimodal score | 59.9 | 67.4 |
| Reasoning score | 60.7 | 83.1 |
| Blended price $/M | $1.56 | $2.00 |
| Output speed | 101 tok/s | 223 tok/s |
| Time to first answer | 21.4 s | 34.8 s |
| Context window | 1M | 1.0M |
| GPQA Diamond | 89.3% | – |
| FrontierMath Tiers 1–3 | 44.9% | – |
| FrontierMath Tier 4 | 17.1% | – |
| OTIS Mock AIME | 92.2% | – |
| SimpleQA Verified | 30.2% | – |
| ProofBench | 14.0% | – |
| LMArena Text | 1472 | 1493 |
| LMArena Hard Prompts | 1488 | 1516 |
| LMArena Coding | 1510 | 1537 |
| LMArena WebDev | 1374 | 1652 |
| LMArena Vision | 1263 | 1315 |
| LMArena Agent | – | 4.2 |
| AA Intelligence Index | 25.7 | 48.2 |
| IFBench | 82.9% | – |
| AA-LCR | 69.0% | 83.0% |
| MMMU-Pro | 74.6% | – |
| AA-Omniscience | 14.8 | 25 |
| Terminal-Bench Hard | 40.9% | – |
| GPQA Diamond (AA) | 91.1% | 93.5% |
| Humanity's Last Exam (AA) | 34.5% | 48.7% |
| SciCode (AA) | – | 58.8% |
| τ²-Bench Telecom (AA) | 96.5% | – |
| AIME (Vals) | 96.5% | – |
| LiveCodeBench | 84.3% | – |
| MMLU-Pro | 86.3% | – |
| IOI | – | 56.6% |
| LegalBench | 77.7% | – |
| CorpFin | 63.7% | – |
| TaxEval | 74.1% | – |
| MedQA | 94.5% | – |
| Terminal-Bench 2.1 (Vals) | 44.2% | 79.0% |
| SWE-bench (Vals) | 72.2% | – |
| GPQA Diamond (Vals) | 88.6% | – |
| Vals Index | 17.6 | 64.5 |
| Kagi LLM Benchmark | 75.0% | – |
| ARC-AGI-1 | 89.5% | – |
| ARC-AGI-2 | 65.1% | – |
| ARC-AGI-3 | 0.1% | – |
| CritPt | 6.6% | 24.9% |
| GDPval (AA) | – | 60.2% |
| τ²-Bench Banking (AA) | – | 50.5% |
| APEX-Agents (AA) | 14.2% | – |
| CaseLaw v2 | 54.5% | – |
| Code Migration | 0.3% | 47.4% |
| Excel Modeling Benchmark | 11.7% | 67.4% |
| Finance Agent v2 | 28.5% | 60.0% |
| Harvey's Legal Agent Benchmark | 0.0% | 23.8% |
| Legal Research Bench | 13.9% | 55.3% |
| MedCode | 32.2% | – |
| MedScribe | 63.4% | – |
| MMMU-Pro (Vals) | 83.5% | – |
| MortgageTax | 45.4% | – |
| MysteryMechanism | – | 36.0% |
| SAGE | 38.2% | – |
| Terminal-Bench 2.0 (Vals) | 40.5% | – |
| Terminal-Bench 4.0 (Vals) | – | 27.8% |
| Terminal-Bench Science | – | 14.3% |
| Vals Multimodal Index | 39.1% | – |
| Vibe Code Bench 1-100 | – | 20.5% |
| Vibe Code Bench v1.1 | 4.1% | 85.9% |
| LMArena Maths | 1467 | 1496 |
| LMArena Creative Writing | 1446 | 1453 |
| LMArena Instruction Following | 1445 | 1483 |
| LMArena Multi-turn | 1480 | 1493 |
| LMArena Longer Queries | 1465 | 1506 |
| LMArena Document | 1439 | 1468 |
| Chess Puzzles | 24.0% | – |
| ForecastBench | 60.7% | – |
Data as of 2026-09-19. Best configuration of each model; every score links to its source on the model pages.
Grok 4.20 vs Muse Spark 1.3: questions
- Is Grok 4.20 better than Muse Spark 1.3?
- Muse Spark 1.3 (max) leads on quality: 69.3 vs 59.9. The BenchLeader Index combines every independent quality benchmark; Muse Spark 1.3 (max) is ahead overall as of 2026-09-19, but check the category scores for your use.
- Is Grok 4.20 better than Muse Spark 1.3 for coding?
- Muse Spark 1.3 scores higher in coding (67 vs 55 on the category index, where 50 is average).
- Is Grok 4.20 better than Muse Spark 1.3 for agentic tasks?
- Muse Spark 1.3 scores higher in agentic tasks (71 vs 52 on the category index, where 50 is average).
- Which is cheaper, Grok 4.20 or Muse Spark 1.3?
- Grok 4.20 is cheaper: $1.56 against $2.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Grok 4.20 or Muse Spark 1.3?
- Muse Spark 1.3 streams faster: 223 against 101 output tokens per second.
- Which has the larger context window?
- Muse Spark 1.3 accepts more context: 1.0M against 1M tokens.