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Muse Spark Open vs Seed 2.1 Pro

Muse Spark Open and Seed 2.1 Pro are closely matched at 44.9 and 45.8 on the LLM Stats Score.

Meta · ByteDance · Updated for 2026

Which is better?

Muse Spark Open and Seed 2.1 Pro are closely matched on the overall LLM Stats Score at 44.9 and 45.8.

In the 7 individual benchmarks reported for both models, Muse Spark Open wins 4; this is a narrower head-to-head signal than the composite indexes.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Muse Spark Open

  • you value its reported benchmark strengths — it wins 4 of 7 exact shared results
  • you want the most recent training data — it shipped Oct 2026
  • you need open weights you can self-host or fine-tune

Choose Seed 2.1 Pro

  • you are already invested in the ByteDance ecosystem

At a glance

The differences that matter most.

Muse Spark Open
Meta
Seed 2.1 Pro
ByteDance
Core performance indexes
LLM Stats Score
44.9
#43
45.8
#39
Reasoning
45.2
#39
47.2
#26
Coding
33.0
#42
31.9
#49
Agents
30.6
#43
31.1
#41
Cost, coverage & limits
Benchmark wins
4 of 7
3 of 7
Input price
$1.25 / M
— / M
Output price
$4.25 / M
— / M
Context window
1,048,576
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Muse Spark Open
Seed 2.1 Pro
Math
31.6#69
40.1#15
Vision
31.2#34
34.5#15
Tool use
23.3#44
24.7#38
Multimodal
33.1#20
37.4#5
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

17 reported for Muse Spark Open · 94 for Seed 2.1 Pro

7 shared

Muse Spark Open outperforms in 4 benchmarks (BabyVision, MCP Atlas, Terminal-Bench 2.1, ZEROBench), while Seed 2.1 Pro is better at 3 benchmarks (SciCode, SimpleVQA, WorldVQA).

Muse Spark Open has a slight edge in benchmark performance.

Mon Oct 19 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Muse Spark Open specifies input context (1,048,576 tokens). Only Muse Spark Open specifies output context (1,048,576 tokens).

Meta
Muse Spark Open
Input1,048,576 tokens
Output1,048,576 tokens
ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Mon Oct 19 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Muse Spark Open and Seed 2.1 Pro support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Muse Spark Open

Text
Images
Audio
Video

Seed 2.1 Pro

Text
Images
Audio
Video

License

Usage and distribution terms

Muse Spark Open is licensed under Muse Model License, while Seed 2.1 Pro uses a proprietary license.

License differences may affect how you can use these models in commercial or open-source projects.

Muse Spark Open

Muse Model License

Open weights

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

Muse Spark Open was released on 2026-10-15, while Seed 2.1 Pro was released on 2026-06-24.

Muse Spark Open is 4 months newer than Seed 2.1 Pro.

Muse Spark Open

Oct 15, 2026

4 days ago

3mo newer
Seed 2.1 Pro

Jun 24, 2026

3 months ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Muse Spark Open and Seed 2.1 Pro side-by-side, then vote on the output you prefer.

Muse Spark Open
✓ Preferred
Seed 2.1 Pro
Open in Playground

FAQ

Common questions about Muse Spark Open vs Seed 2.1 Pro.

Which is better, Muse Spark Open or Seed 2.1 Pro?

Muse Spark Open and Seed 2.1 Pro are closely matched on the LLM Stats Score at 44.9 and 45.8. Muse Spark Open is made by Meta and Seed 2.1 Pro is made by ByteDance. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Muse Spark Open compare to Seed 2.1 Pro in benchmarks?

Muse Spark Open scores MCP Atlas: 89.2%, GPQA: 89.0%, OSWorld-Verified: 80.4%, BabyVision: 80.2%, Terminal-Bench 2.1: 76.4%. Seed 2.1 Pro scores CharXiv-D: 95.5%, MathVision: 94.5%, MathVista: 90.7%, MathVerse: 89.7%, Video-MME: 89.2%.

What are the context window sizes for Muse Spark Open and Seed 2.1 Pro?

Muse Spark Open supports 1.0M tokens and Seed 2.1 Pro supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Muse Spark Open and Seed 2.1 Pro?

Key differences include LLM Stats Score (44.9 vs 45.8), licensing (Muse Model License vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes Muse Spark Open and Seed 2.1 Pro?

Muse Spark Open is developed by Meta and Seed 2.1 Pro is developed by ByteDance.

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