Noometry

Model comparison

GLM-5.3-Flash vs Grok 4.1 Fast

GLM-5.3-Flash is the stronger model overall, scoring 51.8 to 41.4 on the Noometry Index.

Last verified . 21 shared benchmarks.

GLM-5.3-Flash Z.ai (Zhipu)

51.8

Rank #41 Confirmed

Grok 4.1 Fast xAI

41.4

Rank #136 Confirmed

Summary

  • They share 21 benchmarks with published results for both. GLM-5.3-Flash scores higher in 9 categories and Grok 4.1 Fast in 1 category; 10 gaps are clear of the uncertainty.
  • The widest gap is in knowledge, where GLM-5.3-Flash leads 58.4 to 33.1.
  • The biggest single-benchmark swing is ProofBench: 21% for GLM-5.3-Flash and 4% for Grok 4.1 Fast.
  • GLM-5.3-Flash is cheaper at $0.15 / $0.50 per million input/output tokens, against $0.20 / $0.50 for Grok 4.1 Fast.
  • GLM-5.3-Flash accepts more context: 1M tokens versus 128K.
  • GLM-5.3-Flash has downloadable open weights; the other is API-only.

Side by side

GLM-5.3-FlashGrok 4.1 Fast
ProviderZ.ai (Zhipu)xAI
Noometry Index51.841.4
Released2026-08-202025-06-27
WeightsOpenProprietary
Context window1M128K
Max output131K30K
Input $ / M tokens$0.15$0.20
Output $ / M tokens$0.50$0.50
Results tracked4032

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Category by category

Coding GLM-5.3-Flash leads

GLM-5.3-Flash: 53.1 (#31), Grok 4.1 Fast: 34.1 (#245)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena WebDev16091242
LMArena Coding15081411
ALE-Bench303.55394.93
DeepSWE63.4%—
FrontierCode31.8%—
CursorBench36.8%—
FrontierSWE18.1%—
SciCode51.6%—

Agentic & Tool Use Grok 4.1 Fast leads

GLM-5.3-Flash: 34.2 (#47), Grok 4.1 Fast: 36.3 (#39)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
APEX-Agents52.8%—
Berkeley Function Calling Leaderboard—69.6%
τ²-bench Banking—13.1%
GDP.pdf14%—
LMArena Search—1171
Vending-Bench 2—1,107

Reasoning GLM-5.3-Flash leads

GLM-5.3-Flash: 48.0 (#42), Grok 4.1 Fast: 43.4 (#49)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena Hard Prompts14911407
ARC-AGI-265.8%—
SimpleBench—56%
NYT Connections (extended)—87.4%
ARC-AGI-191%—
CritPt15.4%—
Chess Puzzles14%—
Mystery Game Puzzles8%—
DTBench—87.7%
Surface Evolver Bench52.5%—
Bench to the Future 30.15—
Epoch Capabilities Index151.88—
ForecastBench—61

Math GLM-5.3-Flash leads

GLM-5.3-Flash: 53.3 (#47), Grok 4.1 Fast: 31.9 (#221)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
ProofBench21%4%
LMArena Math15001408
FrontierMath (Tiers 1-3)55.8%—
FrontierMath Tier 417.1%—
MathArena Final-Answer Competitions—60.9%
OTIS Mock AIME 2024-202593.9%—

Knowledge GLM-5.3-Flash leads

GLM-5.3-Flash: 58.4 (#36), Grok 4.1 Fast: 33.1 (#207)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena Expert15131399
GPQA Diamond90.2%—
Vectara Hallucination Rate—17.8%

Multimodal GLM-5.3-Flash leads

GLM-5.3-Flash: 42.8 (#27), Grok 4.1 Fast: 37.0 (#76)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena Vision12961201

Multilingual GLM-5.3-Flash leads

GLM-5.3-Flash: 56.0 (#25), Grok 4.1 Fast: 51.0 (#114)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena Non-English14621391
LMArena Chinese15271441
LMArena French14961415
LMArena German14701404
LMArena Japanese14291349
LMArena Korean14461361
LMArena Russian14691387
LMArena Spanish14711413

Instruction Following GLM-5.3-Flash leads

GLM-5.3-Flash: 77.5 (#20), Grok 4.1 Fast: 72.7 (#133)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena Instruction Following14781376

Long Context GLM-5.3-Flash leads

GLM-5.3-Flash: 45.4 (#39), Grok 4.1 Fast: 42.4 (#126)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena Longer Query14821390

Writing & Preference GLM-5.3-Flash leads

GLM-5.3-Flash: 65.3 (#50), Grok 4.1 Fast: 57.2 (#131)

BenchmarkGLM-5.3-FlashGrok 4.1 Fast
LMArena Text14711408
LMArena Creative Writing14421394
LMArena Multi-Turn14671389
EQ-Bench Creative Writing—1327

Frequently asked questions

Is GLM-5.3-Flash better than Grok 4.1 Fast?

GLM-5.3-Flash is the stronger model overall, scoring 51.8 to 41.4 on the Noometry Index.

Which is cheaper, GLM-5.3-Flash or Grok 4.1 Fast?

GLM-5.3-Flash is cheaper. It lists at $0.15 per million input tokens and $0.50 per million output tokens; Grok 4.1 Fast lists at $0.20 and $0.50.

Is GLM-5.3-Flash or Grok 4.1 Fast better for coding?

GLM-5.3-Flash scores higher on coding benchmarks: 53.1 versus 34.1 in the Noometry coding category.

Which has the bigger context window?

GLM-5.3-Flash does, with 1M tokens against 128K.

How many benchmarks do GLM-5.3-Flash and Grok 4.1 Fast share?

21 benchmarks have published results for both models. GLM-5.3-Flash has 40 scored results on Noometry and Grok 4.1 Fast has 32.

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