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Claude Fable 5.1 vs Muse Spark Open

Claude Fable 5.1 leads the LLM Stats Score 53.2 to 44.9. Muse Spark Open is 10.0x cheaper per token.

Anthropic · Meta · Updated for 2026

Which is better?

Claude Fable 5.1 leads the overall LLM Stats Score 53.2 to 44.9, ranking #8 overall.

In the 1 individual benchmarks reported for both models, Claude Fable 5.1 wins 1; this is a narrower head-to-head signal than the composite indexes.

On price, Muse Spark Open is roughly 10.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Muse Spark Open also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

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

Choose Claude Fable 5.1

  • overall performance matters — it scores 53.2 and ranks #8 on LLM Stats
  • your work emphasizes reasoning and agents — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results

Choose Muse Spark Open

  • cost matters — it's about 10.0x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Oct 2026
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Fable 5.1
Anthropic
Muse Spark Open
Meta
Core performance indexes
LLM Stats Score
53.2
#8
44.9
#43
Reasoning
50.7
#12
45.2
#39
Coding
34.2
#34
33.0
#42
Agents
38.2
#11
30.6
#43
Cost, coverage & limits
Benchmark wins
1 of 1
0 of 1
Input price
$10.00 / M
$1.25 / M
Output price
$50.00 / M
$4.25 / M
Context window
1,000,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Fable 5.1
Muse Spark Open
Vision
41.3#3
31.2#34
Tool use
26.8#29
23.3#44
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

7 reported for Claude Fable 5.1 · 17 for Muse Spark Open

1 shared

Claude Fable 5.1 outperforms in 1 benchmarks (GDPval-AA), while Muse Spark Open is better at 0 benchmarks.

Claude Fable 5.1 significantly outperforms across most benchmarks.

Mon Oct 19 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Muse Spark Open costs less

For input processing, Claude Fable 5.1 ($10.00/1M tokens) is 8.0x more expensive than Muse Spark Open ($1.25/1M tokens).

For output processing, Claude Fable 5.1 ($50.00/1M tokens) is 11.8x more expensive than Muse Spark Open ($4.25/1M tokens).

In conclusion, Claude Fable 5.1 is more expensive than Muse Spark Open.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Mon Oct 19 2026 • llm-stats.com
Anthropic
Claude Fable 5.1
Input tokens$10.00
Output tokens$50.00
Best providerAnthropic
Meta
Muse Spark Open
Input tokens$1.25
Output tokens$4.25
Best providerTogether
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Muse Spark Open accepts 1,048,576 input tokens compared to Claude Fable 5.1's 1,000,000 tokens. Muse Spark Open can generate longer responses up to 1,048,576 tokens, while Claude Fable 5.1 is limited to 128,000 tokens.

Anthropic
Claude Fable 5.1
Input1,000,000 tokens
Output128,000 tokens
Meta
Muse Spark Open
Input1,048,576 tokens
Output1,048,576 tokens
Mon Oct 19 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Fable 5.1 and Muse Spark Open support multimodal inputs.

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

Claude Fable 5.1

Text
Images
Audio
Video

Muse Spark Open

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Fable 5.1 is licensed under a proprietary license, while Muse Spark Open uses Muse Model License.

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

Claude Fable 5.1

Proprietary

Closed source

Muse Spark Open

Muse Model License

Open weights

Release Timeline

When each model was launched

Claude Fable 5.1 was released on 2026-09-01, while Muse Spark Open was released on 2026-10-15.

Muse Spark Open is 1 month newer than Claude Fable 5.1.

Claude Fable 5.1

Sep 1, 2026

1 months ago

Muse Spark Open

Oct 15, 2026

2 days ago

1mo newer

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

Provider Availability

Claude Fable 5.1 is available from Anthropic. Muse Spark Open is available from Together.

Claude Fable 5.1

anthropic logo
Anthropic
Input Price:Input: $10.00/1MOutput Price:Output: $50.00/1M

Muse Spark Open

together logo
Together
Input Price:Input: $1.25/1MOutput Price:Output: $4.25/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Fable 5.1 and Muse Spark Open side-by-side, then vote on the output you prefer.

Claude Fable 5.1
✓ Preferred
Muse Spark Open
Open in Playground

FAQ

Common questions about Claude Fable 5.1 vs Muse Spark Open.

Which is better, Claude Fable 5.1 or Muse Spark Open?

Claude Fable 5.1 leads the LLM Stats Score 53.2 to 44.9. Claude Fable 5.1 is made by Anthropic and Muse Spark Open is made by Meta. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Fable 5.1 compare to Muse Spark Open in benchmarks?

Claude Fable 5.1 scores OSWorld 2.0: 77.9%, CursorBench v3.2: 73.4%, Humanity's Last Exam: 65.0%, GDPval-AA: 61.8%, Terminal-Bench 4.0: 55.8%. Muse Spark Open scores MCP Atlas: 89.2%, GPQA: 89.0%, OSWorld-Verified: 80.4%, BabyVision: 80.2%, Terminal-Bench 2.1: 76.4%.

Is Claude Fable 5.1 cheaper than Muse Spark Open?

Muse Spark Open is 8.0x cheaper for input tokens. Claude Fable 5.1 costs $10.00/M input and $50.00/M output via anthropic. Muse Spark Open costs $1.25/M input and $4.25/M output via together.

What are the context window sizes for Claude Fable 5.1 and Muse Spark Open?

Claude Fable 5.1 supports 1.0M tokens and Muse Spark Open supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Fable 5.1 and Muse Spark Open?

Key differences include LLM Stats Score (53.2 vs 44.9), context window (1.0M vs 1.0M), input pricing ($10.00 vs $1.25/M), licensing (Proprietary vs Muse Model License). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Fable 5.1 and Muse Spark Open?

Claude Fable 5.1 is developed by Anthropic and Muse Spark Open is developed by Meta.

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