GPT-5.5 Pro vs Muse Spark 1.3
Muse Spark 1.3 leads the LLM Stats Score 55.1 to 44.9. Muse Spark 1.3 is 540.0x cheaper per token.
OpenAI · Meta · Updated for 2026
Which is better?
Muse Spark 1.3 leads the overall LLM Stats Score 55.1 to 44.9, ranking #4 overall.
On price, Muse Spark 1.3 is roughly 540.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.5 Pro also accepts a larger context window (1,050,000 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-5.5 Pro
- you process long inputs — it offers a 1,050,000 token context window
Choose Muse Spark 1.3
- overall performance matters — it scores 55.1 and ranks #4 on LLM Stats
- cost matters — it's about 540.0x cheaper per token
- you want the most recent training data — it shipped Sep 2026
At a glance
The differences that matter most.
Individual benchmarks
5 reported for GPT-5.5 Pro · 11 for Muse Spark 1.3
GPT-5.5 Pro 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
For input processing, GPT-5.5 Pro ($30.00/1M tokens) is 300.0x more expensive than Muse Spark 1.3 ($0.10/1M tokens).
For output processing, GPT-5.5 Pro ($180.00/1M tokens) is 900.0x more expensive than Muse Spark 1.3 ($0.20/1M tokens).
In conclusion, GPT-5.5 Pro is more expensive than Muse Spark 1.3.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.5 Pro accepts 1,050,000 input tokens compared to Muse Spark 1.3's 1,048,576 tokens. Muse Spark 1.3 can generate longer responses up to 943,718 tokens, while GPT-5.5 Pro is limited to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Both GPT-5.5 Pro and Muse Spark 1.3 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-5.5 Pro
Muse Spark 1.3
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
GPT-5.5 Pro was released on 2026-04-23, while Muse Spark 1.3 was released on 2026-09-02.
Muse Spark 1.3 is 4 months newer than GPT-5.5 Pro.
Apr 23, 2026
4 months ago
Sep 2, 2026
1 weeks ago
4mo newerKnowledge Cutoff
When training data ends
GPT-5.5 Pro has a documented knowledge cutoff of 2025-12-01, while Muse Spark 1.3's cutoff date is not specified.
We can confirm GPT-5.5 Pro's training data extends to 2025-12-01, but cannot make a direct comparison without Muse Spark 1.3's cutoff date.
Dec 2025
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Provider Availability
GPT-5.5 Pro is available from OpenAI. Muse Spark 1.3 is available from Meta Model API.
GPT-5.5 Pro
Muse Spark 1.3
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.5 Pro and Muse Spark 1.3 side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.5 Pro vs Muse Spark 1.3.