Model comparison

GPT-5-Codex vs Muse Spark

Muse Spark is the stronger model overall, scoring 50.6 to 37.9 on the Noometry Index.

Last verified . 0 shared benchmarks.

GPT-5-Codex OpenAI

37.9

Rank #192 Reported

Muse Spark Meta

50.6

Rank #46 Confirmed

Summary

  • The widest gap is in reasoning, where Muse Spark leads 35.9 to 30.9.

Side by side

GPT-5-Codex and Muse Spark specifications
GPT-5-CodexMuse Spark
ProviderOpenAIMeta
Noometry Index37.950.6
Released2025-09-152026-04-08
WeightsProprietaryProprietary
Context window400K—
Max output128K—
Input $ / M tokens$1.25—
Output $ / M tokens$10—
Results tracked327

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Category by category

Coding Muse Spark leads

GPT-5-Codex: 42.4 (#103), Muse Spark: 46.2 (#69)

Coding benchmarks
BenchmarkGPT-5-CodexMuse Spark
SciCode—51.5%
WeirdML54.5%—
LMArena Coding—1481

Agentic & Tool Use Not comparable

GPT-5-Codex: 31.0 (#72), Muse Spark: —

Agentic & Tool Use benchmarks
BenchmarkGPT-5-CodexMuse Spark
Terminal-Bench44.3%—

Reasoning Muse Spark leads

GPT-5-Codex: 30.9 (#83), Muse Spark: 35.9 (#67)

Reasoning benchmarks
BenchmarkGPT-5-CodexMuse Spark
Kagi LLM Benchmark70.3%—
CritPt—11.3%
LMArena Hard Prompts—1474
Epoch Capabilities Index—152.04

Math Not comparable

GPT-5-Codex: —, Muse Spark: 47.8 (#66)

Math benchmarks
BenchmarkGPT-5-CodexMuse Spark
OTIS Mock AIME 2024-2025—88.9%
ProofBench—17%
LMArena Math—1455
FrontierMath (Feb 2025 set)—39%
FrontierMath Tier 4 (v1)—14.6%

Knowledge Not comparable

GPT-5-Codex: —, Muse Spark: 65.7 (#13)

Knowledge benchmarks
BenchmarkGPT-5-CodexMuse Spark
GPQA Diamond—89.8%
Humanity's Last Exam—40.6%
LMArena Expert—1457

Multimodal Not comparable

GPT-5-Codex: —, Muse Spark: 43.4 (#24)

Multimodal benchmarks
BenchmarkGPT-5-CodexMuse Spark
LMArena Vision—1306
LMArena Document—1444

Multilingual Not comparable

GPT-5-Codex: —, Muse Spark: 56.1 (#24)

Multilingual benchmarks
BenchmarkGPT-5-CodexMuse Spark
LMArena Non-English—1464
LMArena Chinese—1509
LMArena French—1497
LMArena German—1497
LMArena Korean—1459
LMArena Russian—1466
LMArena Spanish—1472

Instruction Following Not comparable

GPT-5-Codex: —, Muse Spark: 75.9 (#51)

Instruction Following benchmarks
BenchmarkGPT-5-CodexMuse Spark
LMArena Instruction Following—1442

Long Context Not comparable

GPT-5-Codex: —, Muse Spark: 44.4 (#69)

Long Context benchmarks
BenchmarkGPT-5-CodexMuse Spark
LMArena Longer Query—1451

Writing & Preference Not comparable

GPT-5-Codex: —, Muse Spark: 66.0 (#39)

Writing & Preference benchmarks
BenchmarkGPT-5-CodexMuse Spark
LMArena Text—1474
LMArena Creative Writing—1459
LMArena Multi-Turn—1477

Frequently asked questions

Is GPT-5-Codex better than Muse Spark?

Muse Spark is the stronger model overall, scoring 50.6 to 37.9 on the Noometry Index.

Is GPT-5-Codex or Muse Spark better for coding?

Muse Spark scores higher on coding benchmarks: 46.2 versus 42.4 in the Noometry coding category.

How many benchmarks do GPT-5-Codex and Muse Spark share?

0 benchmarks have published results for both models. GPT-5-Codex has 3 scored results on Noometry and Muse Spark has 27.

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