# Muse Spark vs Step 3.5 Flash

> Muse Spark is the stronger model overall, scoring 50.6 to 42.3 on the Noometry Index.

- Canonical page: https://noometry.com/compare/muse-spark-vs-step-3-5-flash
- Last updated: 2026-10-12
- Shared benchmarks: 16

## Summary

- They share 16 benchmarks with published results for both. Muse Spark scores higher in 8 categories and Step 3.5 Flash in 0 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in knowledge, where Muse Spark leads 65.7 to 39.6.
- Step 3.5 Flash has downloadable open weights; the other is API-only.

## Snapshot

| | Muse Spark | Step 3.5 Flash |
|---|---|---|
| Provider | Meta | StepFun |
| Noometry Index | 50.6 | 42.3 |
| Rank | 46 | 116 |
| Context | — | 256K |
| Input $/M | — | $0.10 |
| Output $/M | — | $0.30 |
| Weights | Proprietary | Open |

## Coding

- Muse Spark: 46.2 (#69)
- Step 3.5 Flash: 42.4 (#105)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Coding | 1481 | 1436 |
| SciCode | 51.5% | — |

## Reasoning

- Muse Spark: 35.9 (#67)
- Step 3.5 Flash: 22.2 (#202)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Hard Prompts | 1474 | 1411 |
| NYT Connections (extended) | — | 28.4% |
| CritPt | 11.3% | — |
| Epoch Capabilities Index | 152.04 | — |

## Math

- Muse Spark: 47.8 (#66)
- Step 3.5 Flash: 42.6 (#84)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Math | 1455 | 1408 |
| MathArena Final-Answer Competitions | — | 66.8% |
| OTIS Mock AIME 2024-2025 | 88.9% | — |
| ProofBench | 17% | — |
| FrontierMath (Feb 2025 set) | 39% | — |
| FrontierMath Tier 4 (v1) | 14.6% | — |

## Knowledge

- Muse Spark: 65.7 (#13)
- Step 3.5 Flash: 39.6 (#132)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Expert | 1457 | 1421 |
| GPQA Diamond | 89.8% | — |
| Humanity's Last Exam | 40.6% | — |

## Multimodal

- Muse Spark: 43.4 (#24)
- Step 3.5 Flash: —

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Vision | 1306 | — |
| LMArena Document | 1444 | — |

## Multilingual

- Muse Spark: 56.1 (#24)
- Step 3.5 Flash: 50.5 (#119)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Non-English | 1464 | 1385 |
| LMArena Chinese | 1509 | 1447 |
| LMArena French | 1497 | 1421 |
| LMArena German | 1497 | 1405 |
| LMArena Korean | 1459 | 1352 |
| LMArena Russian | 1466 | 1385 |
| LMArena Spanish | 1472 | 1419 |
| LMArena Japanese | — | 1354 |

## Instruction Following

- Muse Spark: 75.9 (#51)
- Step 3.5 Flash: 73.1 (#124)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Instruction Following | 1442 | 1385 |

## Long Context

- Muse Spark: 44.4 (#69)
- Step 3.5 Flash: 42.8 (#117)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Longer Query | 1451 | 1402 |

## Writing & Preference

- Muse Spark: 66.0 (#39)
- Step 3.5 Flash: 58.8 (#113)

| Benchmark | Muse Spark | Step 3.5 Flash |
|---|---|---|
| LMArena Text | 1474 | 1403 |
| LMArena Creative Writing | 1459 | 1357 |
| LMArena Multi-Turn | 1477 | 1405 |

## FAQ

### Is Muse Spark better than Step 3.5 Flash?

Muse Spark is the stronger model overall, scoring 50.6 to 42.3 on the Noometry Index.

### Is Muse Spark or Step 3.5 Flash better for coding?

Muse Spark scores higher on coding benchmarks: 46.2 versus 42.4 in the Noometry coding category.

### How many benchmarks do Muse Spark and Step 3.5 Flash share?

16 benchmarks have published results for both models. Muse Spark has 27 scored results on Noometry and Step 3.5 Flash has 19.