Noometry

Model comparison

GLM-5.1 vs GPT-5.5 Instant

GLM-5.1 is the stronger model overall, scoring 47.8 to 42.7 on the Noometry Index.

Last verified . 24 shared benchmarks.

GLM-5.1 Z.ai (Zhipu)

47.8

Rank #59 Confirmed

GPT-5.5 Instant OpenAI

42.7

Rank #110 Confirmed

Summary

  • They share 24 benchmarks with published results for both. GLM-5.1 scores higher in 8 categories and GPT-5.5 Instant in 0 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in math, where GLM-5.1 leads 49.7 to 26.5.
  • The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 93.3% for GLM-5.1 and 68.1% for GPT-5.5 Instant.
  • GLM-5.1 has downloadable open weights; the other is API-only.

Side by side

GLM-5.1GPT-5.5 Instant
ProviderZ.ai (Zhipu)OpenAI
Noometry Index47.842.7
Released2026-04-072026-05-05
WeightsOpenProprietary
Context window200K—
Max output131K—
Input $ / M tokens$1.40—
Output $ / M tokens$4.40—
Results tracked4127

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Category by category

Coding GLM-5.1 leads

GLM-5.1: 48.7 (#55), GPT-5.5 Instant: 44.3 (#74)

BenchmarkGLM-5.1GPT-5.5 Instant
SciCode43.8%48.6%
LMArena Coding14851433
SWE-bench Verified74.2%—
LMArena WebDev1508—
WeirdML57.1%—
ALE-Bench887.1—

Agentic & Tool Use Not comparable

GLM-5.1: 24.9 (#113), GPT-5.5 Instant: —

BenchmarkGLM-5.1GPT-5.5 Instant
APEX-Agents40.9%—
ExploitBench18.1%—
GBAEval0%—
Vending-Bench 25,634—

Reasoning GLM-5.1 leads

GLM-5.1: 39.1 (#60), GPT-5.5 Instant: 24.9 (#155)

BenchmarkGLM-5.1GPT-5.5 Instant
CritPt4.6%0%
Chess Puzzles19%12%
LMArena Hard Prompts14721426
Epoch Capabilities Index149.84142.52
SimpleBench55.1%—
NYT Connections (extended)77.7%—
Thematic Generalization69.8%—

Math GLM-5.1 leads

GLM-5.1: 49.7 (#60), GPT-5.5 Instant: 26.5 (#259)

BenchmarkGLM-5.1GPT-5.5 Instant
FrontierMath (Tiers 1-3)36.8%26.3%
OTIS Mock AIME 2024-202593.3%68.1%
LMArena Math14731420
FrontierMath Tier 4—2.4%
MathArena Final-Answer Competitions67.1%—
ProofBench22.2%—
FrontierMath (Feb 2025 set)33.4%—
FrontierMath Tier 4 (v1)12.5%—

Knowledge GLM-5.1 leads

GLM-5.1: 54.9 (#50), GPT-5.5 Instant: 48.9 (#74)

BenchmarkGLM-5.1GPT-5.5 Instant
GPQA Diamond89.9%82.5%
LMArena Expert14761409
SimpleQA Verified34%—

Multimodal Not comparable

GLM-5.1: —, GPT-5.5 Instant: 40.0 (#52)

BenchmarkGLM-5.1GPT-5.5 Instant
LMArena Vision—1250
LMArena Document—1403

Multilingual GLM-5.1 leads

GLM-5.1: 55.0 (#36), GPT-5.5 Instant: 52.8 (#80)

BenchmarkGLM-5.1GPT-5.5 Instant
LMArena Non-English14471417
LMArena Chinese15151456
LMArena French14741428
LMArena German14651411
LMArena Japanese14341408
LMArena Korean14181392
LMArena Russian14541431
LMArena Spanish14691429

Instruction Following GLM-5.1 leads

GLM-5.1: 76.3 (#42), GPT-5.5 Instant: 74.2 (#100)

BenchmarkGLM-5.1GPT-5.5 Instant
LMArena Instruction Following14511406

Long Context GLM-5.1 leads

GLM-5.1: 44.9 (#53), GPT-5.5 Instant: 43.4 (#96)

BenchmarkGLM-5.1GPT-5.5 Instant
LMArena Longer Query14661422

Writing & Preference GLM-5.1 leads

GLM-5.1: 66.9 (#31), GPT-5.5 Instant: 61.8 (#85)

BenchmarkGLM-5.1GPT-5.5 Instant
LMArena Text14611419
LMArena Creative Writing14531419
LMArena Multi-Turn14721433
EQ-Bench Creative Writing1592—

Frequently asked questions

Is GLM-5.1 better than GPT-5.5 Instant?

GLM-5.1 is the stronger model overall, scoring 47.8 to 42.7 on the Noometry Index.

Is GLM-5.1 or GPT-5.5 Instant better for coding?

GLM-5.1 scores higher on coding benchmarks: 48.7 versus 44.3 in the Noometry coding category.

How many benchmarks do GLM-5.1 and GPT-5.5 Instant share?

24 benchmarks have published results for both models. GLM-5.1 has 41 scored results on Noometry and GPT-5.5 Instant has 27.

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