Model comparison

GPT-5.4 vs Muse Glimmer

GPT-5.4 is the stronger model overall, scoring 59.4 to 41.7 on the Noometry Index.

Last verified . 15 shared benchmarks.

GPT-5.4 OpenAI

59.4

Rank #16 Confirmed

Muse Glimmer Meta

41.7

Rank #131 Confirmed

Summary

  • They share 15 benchmarks with published results for both. GPT-5.4 scores higher in 8 categories and Muse Glimmer in 0 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where GPT-5.4 leads 61.8 to 25.7.
  • The biggest single-benchmark swing is CritPt: 23.4% for GPT-5.4 and 2.6% for Muse Glimmer.
  • Muse Glimmer has downloadable open weights; the other is API-only.

Side by side

GPT-5.4 and Muse Glimmer specifications
GPT-5.4Muse Glimmer
ProviderOpenAIMeta
Noometry Index59.441.7
Released2026-03-052026-08-10
WeightsProprietaryOpen
Context window1.05M—
Max output128K—
Input $ / M tokens$2.50—
Output $ / M tokens$15—
Results tracked6815

Sponsored placements are available on pages like this one. Advertise on Noometry

Category by category

Coding GPT-5.4 leads

GPT-5.4: 52.6 (#33), Muse Glimmer: 40.4 (#142)

Coding benchmarks
BenchmarkGPT-5.4Muse Glimmer
LMArena WebDev14651355
SciCode56.6%44.9%
LMArena Coding14971416
SWE-bench Verified76.9%—
DeepSWE51.8%—
GSO31.4%—
WeirdML77.7%—
MirrorCode15.6%—
ALE-Bench1,607—
AlgoTune1.85—

Agentic & Tool Use Not comparable

GPT-5.4: 46.5 (#13), Muse Glimmer: —

Agentic & Tool Use benchmarks
BenchmarkGPT-5.4Muse Glimmer
Terminal-Bench81.8%—
APEX-Agents52.4%—
τ²-bench Banking39.4%—
DeepResearch Bench35.1%—
PostTrainBench19%—
GBAEval45.1%—
LMArena Search1197—
METR Time Horizons74.3%—
Vending-Bench 26,144—

Reasoning GPT-5.4 leads

GPT-5.4: 61.8 (#19), Muse Glimmer: 25.7 (#144)

Reasoning benchmarks
BenchmarkGPT-5.4Muse Glimmer
CritPt23.4%2.6%
LMArena Hard Prompts14851396
ARC-AGI-274%—
Kagi LLM Benchmark63.8%—
NYT Connections (extended)91.3%—
ARC-AGI-193.7%—
Chess Puzzles44%—
EnigmaEval16%—
Thematic Generalization80%—
EBR-Bench25.4%—
Mystery Game Puzzles37%—
DTBench94.4%—
LMCA52%—
Epoch Capabilities Index156.81—
ForecastBench59.5—

Math GPT-5.4 leads

GPT-5.4: 73.5 (#19), Muse Glimmer: 38.8 (#125)

Knowledge GPT-5.4 leads

GPT-5.4: 65.3 (#14), Muse Glimmer: 38.5 (#143)

Knowledge benchmarks
BenchmarkGPT-5.4Muse Glimmer
LMArena Expert15071386
GPQA Diamond93.3%—
Humanity's Last Exam36.2%—
SimpleQA Verified45.1%—
Vectara Hallucination Rate7%—

Multimodal Not comparable

GPT-5.4: 43.7 (#20), Muse Glimmer: —

Multimodal benchmarks
BenchmarkGPT-5.4Muse Glimmer
LMArena Vision1303—
Blueprint-Bench 227.1%—
Furniture Assembly37.5%—
LMArena Document1471—

Multilingual GPT-5.4 leads

GPT-5.4: 56.2 (#23), Muse Glimmer: 50.5 (#122)

Multilingual benchmarks
BenchmarkGPT-5.4Muse Glimmer
LMArena Non-English14651384
LMArena Chinese15191412
LMArena Russian14801390
LMArena French1493—
LMArena German1472—
LMArena Japanese1485—
LMArena Korean1448—
LMArena Spanish1454—

Instruction Following GPT-5.4 leads

GPT-5.4: 77.1 (#27), Muse Glimmer: 72.6 (#135)

Instruction Following benchmarks
BenchmarkGPT-5.4Muse Glimmer
LMArena Instruction Following14691375

Long Context GPT-5.4 leads

GPT-5.4: 50.3 (#8), Muse Glimmer: 42.1 (#129)

Long Context benchmarks
BenchmarkGPT-5.4Muse Glimmer
LMArena Longer Query14731382
CL-bench27.9%—
CL-bench Life21.7%—

Writing & Preference GPT-5.4 leads

GPT-5.4: 71.9 (#17), Muse Glimmer: 57.5 (#126)

Writing & Preference benchmarks
BenchmarkGPT-5.4Muse Glimmer
LMArena Text14691389
LMArena Creative Writing14391339
LMArena Multi-Turn14821399
EQ-Bench Creative Writing1840—
EQ-Bench 41272—

Frequently asked questions

Is GPT-5.4 better than Muse Glimmer?

GPT-5.4 is the stronger model overall, scoring 59.4 to 41.7 on the Noometry Index.

Is GPT-5.4 or Muse Glimmer better for coding?

GPT-5.4 scores higher on coding benchmarks: 52.6 versus 40.4 in the Noometry coding category.

How many benchmarks do GPT-5.4 and Muse Glimmer share?

15 benchmarks have published results for both models. GPT-5.4 has 68 scored results on Noometry and Muse Glimmer has 15.

Related comparisons

Go deeper