Model Comparison
GPT-5.6 Terra vs Muse Spark 1.1Which is better in 2026?
GPT-5.6 Terra shows notably better performance in the majority of benchmarks. Muse Spark 1.1 is 2.8x cheaper per token.
Verdict: GPT-5.6 Terra vs Muse Spark 1.1 — which is better?
GPT-5.6 Terra (by OpenAI) and Muse Spark 1.1 (by Meta) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.
GPT-5.6 Terra outperforms in 2 benchmarks (SWE-Bench Pro, Terminal-Bench 2.1), while Muse Spark 1.1 is better at 1 benchmark (Toolathlon). GPT-5.6 Terra shows notably better performance in the majority of benchmarks.
On price, Muse Spark 1.1 is roughly 2.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.6 Terra also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Choose GPT-5.6 Terra if…
- you want the strongest raw capability — it leads on 2 of 3 shared benchmarks
- you process long inputs — it offers a 1,050,000 token context window
Choose Muse Spark 1.1 if…
- cost matters — it's about 2.8x cheaper per token
Performance Benchmarks
Comparative analysis across standard metrics
GPT-5.6 Terra outperforms in 2 benchmarks (SWE-Bench Pro, Terminal-Bench 2.1), while Muse Spark 1.1 is better at 1 benchmark (Toolathlon).
GPT-5.6 Terra shows notably better performance in the majority of benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-5.6 Terra ($2.50/1M tokens) is 2.0x more expensive than Muse Spark 1.1 ($1.25/1M tokens).
For output processing, GPT-5.6 Terra ($15.00/1M tokens) is 3.5x more expensive than Muse Spark 1.1 ($4.25/1M tokens).
In conclusion, GPT-5.6 Terra is more expensive than Muse Spark 1.1.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.6 Terra accepts 1,050,000 input tokens compared to Muse Spark 1.1's 1,048,576 tokens. Muse Spark 1.1 can generate longer responses up to 131,072 tokens, while GPT-5.6 Terra is limited to 128,000 tokens.
Input Capabilities
Supported data types and modalities
Both GPT-5.6 Terra and Muse Spark 1.1 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-5.6 Terra
Muse Spark 1.1
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
Both models were released on 2026-07-09.
They likely represent similar generations of model development.
Jul 9, 2026
1 weeks ago
Jul 9, 2026
1 weeks ago
Knowledge Cutoff
When training data ends
GPT-5.6 Terra has a documented knowledge cutoff of 2026-02-16, while Muse Spark 1.1's cutoff date is not specified.
We can confirm GPT-5.6 Terra's training data extends to 2026-02-16, but cannot make a direct comparison without Muse Spark 1.1's cutoff date.
Feb 2026
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Provider Availability
GPT-5.6 Terra is available from OpenAI. Muse Spark 1.1 is available from Meta Model API.
GPT-5.6 Terra
Muse Spark 1.1
Outputs Comparison
Key Takeaways
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against GPT-5.6 Terra and Muse Spark 1.1 side-by-side, then vote on the output you prefer.
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FAQ
Common questions about GPT-5.6 Terra vs Muse Spark 1.1.