Skip to main content
BenchLM
Data

Muse Spark Open vs Step 5 Preview

Updated October 15, 2026. Rank says Step 5 Preview is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.

Share or export
Share on XLinkedInAPI/MCP

Decision reading

Step 5 Preview has the higher public point estimate, 69.44 versus 62.66. Their conditional score ranges overlap. These ranges do not establish rank confidence. 3 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

Model A
Meta logo
Muse Spark Open

Meta

62.66/100

Estimated · Public rank #45

Conditional range 48.3–77.0

Model B
StepFun logo
Step 5 Preview

StepFun

69.44/100

Estimated · Public rank #20

Conditional range 59.7–79.2

Shared results
3
Muse Spark Open only
4
Step 5 Preview only
21
Like-for-like categories
1 / 8
Estimated: Muse Spark Open and Step 5 Preview. Conditional ranges do not establish rank confidence.How the comparison works

Which one for your work

Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.

No workload recommendation clears the current evidence threshold.

Use the matched evidence, workload costs, and sourced specifications below instead of treating a point score as a universal answer.

Show secondary and unsupported calls

  • Coding work

    Code generation, repair, and software-engineering tasks

    Not enough matched evidence

    Step 5 Preview is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like.

    Confidence: limited

  • Agentic work

    Tool use, computer use, and multi-step task completion

    Not enough matched evidence

    Muse Spark Open and Step 5 Preview are scored on Estimated evidence for agentic, so the reading is directional rather than like-for-like.

    Confidence: limited

  • Long documents

    Prompts that approach the documented context limit

    No clear pick

    The documented context windows are equal.

    Confidence: documented

  • Chat turn cost

    1K fresh input + 500 output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    Confidence: listed-rates

  • Cache-heavy agent loop cost

    200K cached + 20K fresh input + 10K output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    Confidence: listed-rates

  • Repository review cost

    50K fresh input + 3K output tokens

    Not enough matched evidence

    A complete comparable API-rate estimate is not available for both models.

    Confidence: listed-rates

Which one for a specific job

Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.

The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.

56.1Muse Spark Open60.5Step 5 Preview

Directional only · BenchAlign v5.8

Step 5 Preview has the higher coding point estimate. Conditional score ranges do not establish rank confidence.

Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.

Open the coding leaderboardShortlist models for this job
Same basis rules as the category table below

What is actually comparable

Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.

2 categories rest on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.

Shape of the matched evidence

Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.

A shared-evidence shape is not available.

BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.

Category results, on a stated basis

Each row shows the public-lane category score for both models: the BenchAlign v5.8 lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.

Knowledge

Like-for-like
Muse Spark Open
64.6
Supported · #38/184
Step 5 Preview
68.7
Supported · #22/184
Basis
BenchAlign v5.8 lane · 0 vs 2 public rows
Reading
Step 5 Preview leads · intervals overlap

Agentic

Directional only
Muse Spark Open
60.2
Estimated · #27/127
Step 5 Preview
65.4
Estimated · #18/127
Basis
BenchAlign v5.8 lane · 4 vs 13 public rows
Reading
Directional only

Coding

Directional only
Muse Spark Open
56.1
Supported · #29/150
Step 5 Preview
60.5
Estimated · #20/150
Basis
BenchAlign v5.8 lane · 0 vs 6 public rows
Reading
Directional only

Reasoning

Not comparable
Muse Spark Open
79.6
Unranked · 2 rankable rows
Step 5 Preview
83.4
Unranked · 2 rankable rows
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multimodal

Not comparable
Muse Spark Open
83.6
Unranked · 4 rankable rows
Step 5 Preview
74.6
#24/54
Basis
Provisional lane · 0 vs 2 weighted rows
Reading
Not comparable

Multilingual

Not comparable
Muse Spark Open
Not ranked
Step 5 Preview
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Instruction following

Not comparable
Muse Spark Open
Not ranked
Step 5 Preview
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Math

Not comparable
Muse Spark Open
Not ranked
Step 5 Preview
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.

Supported evidence per lane · bars run 0–100Methodology

What each workload costs

Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.

Chat turn

1K fresh input + 500 output tokens

Muse Spark Open
API rate not published
Fits in one request
Step 5 Preview
$0.00235
Fits in one request

Muse Spark Open has no comparable published API token rate.

Repository review

50K fresh input + 3K output tokens

Muse Spark Open
API rate not published
Fits in one request
Step 5 Preview
$0.0581
Fits in one request

Muse Spark Open has no comparable published API token rate.

Cache-heavy agent loop

200K cached + 20K fresh input + 10K output tokens

Muse Spark Open
API rate not published
Fits in one request
Cached-input rate unavailable
Step 5 Preview
$0.057
Fits in one request

Muse Spark Open has no comparable published API token rate.

Cached input falls back to the list input rate only where a cached rate is unpublished

Specification differences

Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.

Cached-input rate

A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.

Muse Spark Open

No comparable hosted API rate

Meta AI Research blog

Step 5 Preview

$0.05 per 1M cached input tokens

StepFun pricing and rate limits

Reasoning profile

Muse Spark Open

Reasoning

Step 5 Preview

Reasoning

Weight access

Muse Spark Open

Open Weight

Step 5 Preview

Open Weight

License

Muse Spark Open

Open Weight

Step 5 Preview

Open Weight

Release date

Muse Spark Open

2026-10-15

Step 5 Preview

2026-09-20

If you already use one of these models

Deployment change
The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
Quality signal
Step 5 Preview has the higher public point estimate, 69.44 versus 62.66. Their conditional score ranges overlap. These ranges do not establish rank confidence.
Workload cost
A complete comparable API-rate estimate is not available for both models.
Context tradeoff
Both models list 1M.
Run the same representative tasks against both endpoints before changing production traffic.

Questions

Which is better, Muse Spark Open or Step 5 Preview?

Step 5 Preview has the higher public point estimate, 69.44 versus 62.66. Their conditional score ranges overlap. These ranges do not establish rank confidence. The page therefore keeps the decision tied to the specific documented workload.

Which is better for coding, Muse Spark Open or Step 5 Preview?

Step 5 Preview scores higher for coding on the public lane, 60.5 to 56.1. Step 5 Preview is scored on Estimated evidence for coding, so the reading is directional rather than like-for-like. BenchLM does not name a winner for coding from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which is better for agentic tasks, Muse Spark Open or Step 5 Preview?

Step 5 Preview scores higher for agentic tasks on the public lane, 65.4 to 60.2. Muse Spark Open and Step 5 Preview are scored on Estimated evidence for agentic tasks, so the reading is directional rather than like-for-like. BenchLM does not name a winner for agentic tasks from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which costs less, Muse Spark Open or Step 5 Preview?

Both models do not have comparable published API token rates, so this page does not name a universal price winner.

Which has the larger context window, Muse Spark Open or Step 5 Preview?

Both models list the same context window, 1M.

Benchmark evidence

The full public result ledger is available for audit without forcing a wide desktop table onto a phone.

Browse raw public benchmark evidence28 rows

Agentic

  • JobBench

    Muse Spark Open61.8%
    Source
    Step 5 Preview59.0%
    Source

    Muse Spark Open leads this result

  • MCP Atlas

    Muse Spark Open89.2%
    Source
    Step 5 Preview85.6%
    Source

    Muse Spark Open leads this result

  • HLE w/ tools

    Muse Spark Open61.0%
    Source
    Step 5 Preview—

    Not directly comparable

  • Toolathlon-Verified

    Muse Spark Open72.8%
    Source
    Step 5 Preview74.1%
    Source

    Step 5 Preview leads this result

  • Terminal-Bench 2.1

    Muse Spark Open—
    Step 5 Preview85.0%
    Source

    Not directly comparable

  • Terminal-Bench 4.0

    Muse Spark Open—
    Step 5 Preview33.30%
    Source

    Not directly comparable

  • CyberGym

    Muse Spark Open—
    Step 5 Preview84.7%
    Source

    Not directly comparable

  • AutomationBench

    Muse Spark Open—
    Step 5 Preview44.0%
    Source

    Not directly comparable

  • APEX-Agents

    Muse Spark Open—
    Step 5 Preview37.8%
    Source

    Not directly comparable

  • DRACO

    Muse Spark Open—
    Step 5 Preview83.3%
    Source

    Not directly comparable

  • BrowseComp

    Muse Spark Open—
    Step 5 Preview88.7%
    Source

    Not directly comparable

  • Agents' Last Exam

    Muse Spark Open—
    Step 5 Preview29.5%
    Source

    Not directly comparable

  • Hermes Index

    Muse Spark Open—
    Step 5 Preview32.8%
    Source

    Not directly comparable

  • Hermes Bench

    Muse Spark Open—
    Step 5 Preview69.2%
    Source

    Not directly comparable

Coding

  • DeepSWE

    Muse Spark Open—
    Step 5 Preview67.7%
    Source

    Not directly comparable

  • Terminal-Bench 2.1

    Muse Spark Open—
    Step 5 Preview85.0%
    Source

    Not directly comparable

  • SciCode

    Muse Spark Open—
    Step 5 Preview58.9%
    Source

    Not directly comparable

  • ProgramBench

    Muse Spark Open—
    Step 5 Preview80.5%
    Source

    Not directly comparable

  • sweMarathon

    Muse Spark Open—
    Step 5 Preview72.7%
    Source

    Not directly comparable

  • MLS-Bench Lite

    Muse Spark Open—
    Step 5 Preview40.5%
    Source

    Not directly comparable

Reasoning

  • CritPt

    Muse Spark Open—
    Step 5 Preview20.9%
    Source

    Not directly comparable

Multimodal

  • ZeroBench

    Muse Spark Open50.0%
    Source
    Step 5 Preview—

    Not directly comparable

  • BabyVision

    Muse Spark Open80.2%
    Source
    Step 5 Preview—

    Not directly comparable

  • SimpleVQA

    Muse Spark Open73.6%
    Source
    Step 5 Preview—

    Not directly comparable

  • OfficeQA Pro

    Muse Spark Open—
    Step 5 Preview60.3%
    Source

    Not directly comparable

  • MMMU-Pro

    Muse Spark Open—
    Step 5 Preview76%
    Source

    Not directly comparable

Knowledge

  • GPQA-D

    Muse Spark Open—
    Step 5 Preview93.5%
    Source

    Not directly comparable

  • HLE

    Muse Spark Open—
    Step 5 Preview46.5%
    Source

    Not directly comparable

28 public results · 3 shared

Related comparisons

Compare API pricingRead the methodologyOpen the model selector

Watch Muse Spark Open vs Step 5 Preview

One weekly email when material rank, price, or benchmark evidence changes make this matchup worth revisiting.

Read a sample issue

Join 5,500+ readers.

Last updated October 15, 2026