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GPT-5.1 Medium vs Muse Spark 1.3

Muse Spark 1.3 leads the LLM Stats Score 54.3 to 31.2. Muse Spark 1.3 is 1.7x cheaper per token.

OpenAI · Meta · Updated for 2026

Which is better?

Muse Spark 1.3 leads the overall LLM Stats Score 54.3 to 31.2, ranking #6 overall.

On price, Muse Spark 1.3 is roughly 1.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Muse Spark 1.3 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 GPT-5.1 Medium

  • you want predictable pricing at $1.25/M input and $10.00/M output

Choose Muse Spark 1.3

  • overall performance matters — it scores 54.3 and ranks #6 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • cost matters — it's about 1.7x 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 Sep 2026

At a glance

The differences that matter most.

GPT-5.1 Medium
OpenAI
Muse Spark 1.3
Meta
Core performance indexes
LLM Stats Score
31.2
#112
54.3
#6
Reasoning
31.0
#111
51.8
#8
Cost, coverage & limits
Benchmark wins
—
—
Input price
$1.25 / M
$1.25 / M
Output price
$10.00 / M
$4.25 / M
Context window
400,000
1,048,576

Individual benchmarks

1 reported for GPT-5.1 Medium · 11 for Muse Spark 1.3

No common benchmarks found

GPT-5.1 Medium and Muse Spark 1.3don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Muse Spark 1.3 costs less

For input processing, GPT-5.1 Medium ($1.25/1M tokens) costs the same as Muse Spark 1.3 ($1.25/1M tokens).

For output processing, GPT-5.1 Medium ($10.00/1M tokens) is 2.4x more expensive than Muse Spark 1.3 ($4.25/1M tokens).

In conclusion, GPT-5.1 Medium is more expensive than Muse Spark 1.3.*

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

Lowest available price from all providers
Sun Sep 20 2026 • llm-stats.com
OpenAI
GPT-5.1 Medium
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
Meta
Muse Spark 1.3
Input tokens$1.25
Output tokens$4.25
Best providerMeta
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Muse Spark 1.3 accepts 1,048,576 input tokens compared to GPT-5.1 Medium's 400,000 tokens. Muse Spark 1.3 can generate longer responses up to 943,718 tokens, while GPT-5.1 Medium is limited to 128,000 tokens.

OpenAI
GPT-5.1 Medium
Input400,000 tokens
Output128,000 tokens
Meta
Muse Spark 1.3
Input1,048,576 tokens
Output943,718 tokens
Sun Sep 20 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both GPT-5.1 Medium and Muse Spark 1.3 support multimodal inputs.

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

GPT-5.1 Medium

Text
Images
Audio
Video

Muse Spark 1.3

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

GPT-5.1 Medium

Proprietary

Closed source

Muse Spark 1.3

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.1 Medium was released on 2025-11-12, while Muse Spark 1.3 was released on 2026-09-02.

Muse Spark 1.3 is 10 months newer than GPT-5.1 Medium.

GPT-5.1 Medium

Nov 12, 2025

10 months ago

Muse Spark 1.3

Sep 2, 2026

2 weeks ago

9mo 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

GPT-5.1 Medium is available from OpenAI. Muse Spark 1.3 is available from Meta Model API.

GPT-5.1 Medium

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M

Muse Spark 1.3

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

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against GPT-5.1 Medium and Muse Spark 1.3 side-by-side, then vote on the output you prefer.

GPT-5.1 Medium
✓ Preferred
Muse Spark 1.3
Open in Playground

FAQ

Common questions about GPT-5.1 Medium vs Muse Spark 1.3.

Which is better, GPT-5.1 Medium or Muse Spark 1.3?

Muse Spark 1.3 leads the LLM Stats Score 54.3 to 31.2. GPT-5.1 Medium is made by OpenAI and Muse Spark 1.3 is made by Meta. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-5.1 Medium compare to Muse Spark 1.3 in benchmarks?

GPT-5.1 Medium scores AIME 2025: 98.4%. Muse Spark 1.3 scores MRCR v2 (8-needle): 98.5%, MRCR v2 (8-needle, 512K-1M): 98.1%, DeepSearchQA: 89.4%, Terminal-Bench 2.1: 88.8%, DeepSWE 1.1: 75.4%.

Is GPT-5.1 Medium cheaper than Muse Spark 1.3?

Both models cost $1.25 per million input tokens.

What are the context window sizes for GPT-5.1 Medium and Muse Spark 1.3?

GPT-5.1 Medium supports 400K tokens and Muse Spark 1.3 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 GPT-5.1 Medium and Muse Spark 1.3?

Key differences include LLM Stats Score (31.2 vs 54.3), context window (400K vs 1.0M). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5.1 Medium and Muse Spark 1.3?

GPT-5.1 Medium is developed by OpenAI and Muse Spark 1.3 is developed by Meta.

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