# Muse Spark 1.3 vs Step 5 Preview

> Muse Spark 1.3 is the stronger model overall, scoring 54.8 to 47.9 on the Noometry Index.

- Canonical page: https://noometry.com/compare/muse-spark-1-3-vs-step-5-preview
- Last updated: 2026-10-11
- Shared benchmarks: 18

## Summary

- They share 18 benchmarks with published results for both. Muse Spark 1.3 scores higher in 9 categories and Step 5 Preview in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in math, where Muse Spark 1.3 leads 73.1 to 46.1.
- The biggest single-benchmark swing is ProofBench: 58% for Muse Spark 1.3 and 42% for Step 5 Preview.
- Step 5 Preview is cheaper at $1 / $2.70 per million input/output tokens, against $1.25 / $4.25 for Muse Spark 1.3.
- Muse Spark 1.3 accepts more context: 1.05M tokens versus 1.02M.

## Snapshot

| | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| Provider | Meta | StepFun |
| Noometry Index | 54.8 | 47.9 |
| Rank | 27 | 58 |
| Context | 1.05M | 1.02M |
| Input $/M | $1.25 | $1 |
| Output $/M | $4.25 | $2.70 |
| Weights | Proprietary | Proprietary |

## Coding

- Muse Spark 1.3: 56.6 (#21)
- Step 5 Preview: 51.8 (#36)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| LMArena WebDev | 1657 | 1564 |
| SciCode | 59.7% | 58.9% |
| LMArena Coding | 1514 | 1480 |
| CursorBench | 41.6% | — |

## Agentic & Tool Use

- Muse Spark 1.3: 38.6 (#30)
- Step 5 Preview: —

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| APEX-Agents | 57.8% | — |
| GDP.pdf | 27.6% | — |

## Reasoning

- Muse Spark 1.3: 54.0 (#27)
- Step 5 Preview: 40.0 (#57)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| CritPt | 26% | 20.9% |
| LMArena Hard Prompts | 1503 | 1465 |
| NYT Connections (extended) | 85.1% | — |
| Chess Puzzles | 38% | — |
| Mystery Game Puzzles | 25% | — |
| DTBench | 96.5% | — |
| LMCA | 53.9% | — |
| Bench to the Future 3 | 0.14 | — |
| Epoch Capabilities Index | 156.75 | — |

## Math

- Muse Spark 1.3: 73.1 (#21)
- Step 5 Preview: 46.1 (#72)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| ProofBench | 58% | 42% |
| LMArena Math | 1494 | 1470 |
| FrontierMath (Tiers 1-3) | 74.4% | — |
| FrontierMath Tier 4 | 46.3% | — |
| OTIS Mock AIME 2024-2025 | 99.2% | — |

## Knowledge

- Muse Spark 1.3: 42.6 (#95)
- Step 5 Preview: 41.2 (#112)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| LMArena Expert | 1516 | 1470 |

## Multimodal

- Muse Spark 1.3: 43.7 (#22)
- Step 5 Preview: 41.0 (#41)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| LMArena Vision | 1309 | 1267 |
| LMArena Document | 1471 | — |

## Multilingual

- Muse Spark 1.3: 57.4 (#8)
- Step 5 Preview: 53.8 (#54)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| LMArena Non-English | 1481 | 1432 |
| LMArena Chinese | 1529 | 1519 |
| LMArena Russian | 1490 | 1436 |
| LMArena Spanish | 1490 | 1439 |
| LMArena French | 1524 | — |
| LMArena German | 1515 | — |
| LMArena Japanese | 1474 | — |
| LMArena Korean | 1501 | — |

## Instruction Following

- Muse Spark 1.3: 77.5 (#22)
- Step 5 Preview: 76.0 (#50)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| LMArena Instruction Following | 1477 | 1444 |

## Long Context

- Muse Spark 1.3: 45.6 (#32)
- Step 5 Preview: 44.5 (#64)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| LMArena Longer Query | 1488 | 1455 |

## Writing & Preference

- Muse Spark 1.3: 73.6 (#9)
- Step 5 Preview: 62.8 (#71)

| Benchmark | Muse Spark 1.3 | Step 5 Preview |
|---|---|---|
| LMArena Text | 1490 | 1442 |
| LMArena Creative Writing | 1455 | 1410 |
| LMArena Multi-Turn | 1482 | 1447 |
| EQ-Bench Creative Writing | 1906 | — |

## FAQ

### Is Muse Spark 1.3 better than Step 5 Preview?

Muse Spark 1.3 is the stronger model overall, scoring 54.8 to 47.9 on the Noometry Index.

### Which is cheaper, Muse Spark 1.3 or Step 5 Preview?

Step 5 Preview is cheaper. It lists at $1 per million input tokens and $2.70 per million output tokens; Muse Spark 1.3 lists at $1.25 and $4.25.

### Is Muse Spark 1.3 or Step 5 Preview better for coding?

Muse Spark 1.3 scores higher on coding benchmarks: 56.6 versus 51.8 in the Noometry coding category.

### Which has the bigger context window?

Muse Spark 1.3 does, with 1.05M tokens against 1.02M.

### How many benchmarks do Muse Spark 1.3 and Step 5 Preview share?

18 benchmarks have published results for both models. Muse Spark 1.3 has 37 scored results on Noometry and Step 5 Preview has 18.