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GPT-5 Codex vs Muse Spark 1.3

Muse Spark 1.3 leads the LLM Stats Score 55.3 to 26.8.

OpenAI · Meta · Updated for 2026

Which is better?

Muse Spark 1.3 leads the overall LLM Stats Score 55.3 to 26.8, ranking #5 overall.

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

Choose GPT-5 Codex

  • you are already invested in the OpenAI ecosystem

Choose Muse Spark 1.3

  • overall performance matters — it scores 55.3 and ranks #5 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you want the most recent training data — it shipped Sep 2026

At a glance

The differences that matter most.

GPT-5 Codex
OpenAI
Muse Spark 1.3
Meta
Core performance indexes
LLM Stats Score
26.8
#138
55.3
#5
Reasoning
26.7
#137
52.8
#7
Coding
19.4
#99
41.7
#10
Cost, coverage & limits
Benchmark wins
—
—
Input price
— / M
$0.10 / M
Output price
— / M
$0.20 / M
Context window
—
1,048,576

Individual benchmarks

1 reported for GPT-5 Codex · 11 for Muse Spark 1.3

No common benchmarks found

GPT-5 Codex 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

Context Window

Maximum input and output token capacity

Only Muse Spark 1.3 specifies input context (1,048,576 tokens). Only Muse Spark 1.3 specifies output context (943,718 tokens).

OpenAI
GPT-5 Codex
Input- tokens
Output- tokens
Meta
Muse Spark 1.3
Input1,048,576 tokens
Output943,718 tokens
Sat Sep 05 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Muse Spark 1.3 supports multimodal inputs, whereas GPT-5 Codex does not.

Muse Spark 1.3 can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-5 Codex

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 Codex

Proprietary

Closed source

Muse Spark 1.3

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5 Codex was released on 2025-09-15, while Muse Spark 1.3 was released on 2026-09-02.

Muse Spark 1.3 is 12 months newer than GPT-5 Codex.

GPT-5 Codex

Sep 15, 2025

11 months ago

Muse Spark 1.3

Sep 2, 2026

2 days ago

11mo newer

Knowledge Cutoff

When training data ends

GPT-5 Codex has a documented knowledge cutoff of 2024-09-30, while Muse Spark 1.3's cutoff date is not specified.

We can confirm GPT-5 Codex's training data extends to 2024-09-30, but cannot make a direct comparison without Muse Spark 1.3's cutoff date.

GPT-5 Codex

Sep 2024

Muse Spark 1.3

—

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against GPT-5 Codex and Muse Spark 1.3 side-by-side, then vote on the output you prefer.

GPT-5 Codex
✓ Preferred
Muse Spark 1.3
Open in Playground

FAQ

Common questions about GPT-5 Codex vs Muse Spark 1.3.

Which is better, GPT-5 Codex or Muse Spark 1.3?

Muse Spark 1.3 leads the LLM Stats Score 55.3 to 26.8. GPT-5 Codex 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 Codex compare to Muse Spark 1.3 in benchmarks?

GPT-5 Codex scores SWE-Bench Verified: 74.5%. 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%.

What are the context window sizes for GPT-5 Codex and Muse Spark 1.3?

GPT-5 Codex supports an unknown number of 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 Codex and Muse Spark 1.3?

Key differences include LLM Stats Score (26.8 vs 55.3), multimodal support (no vs yes). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5 Codex and Muse Spark 1.3?

GPT-5 Codex is developed by OpenAI and Muse Spark 1.3 is developed by Meta.

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