Noometry

Model comparison

GPT-6 Astra vs Grok 4 Fast

GPT-6 Astra is the stronger model overall, scoring 70.8 to 39.4 on the Noometry Index.

Last verified . 24 shared benchmarks.

GPT-6 Astra OpenAI

70.8

Rank #1 Confirmed

Grok 4 Fast xAI

39.4

Rank #167 Confirmed

Summary

  • They share 24 benchmarks with published results for both. GPT-6 Astra scores higher in 8 categories and Grok 4 Fast in 1 category; 9 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where GPT-6 Astra leads 85.1 to 22.2.
  • The biggest single-benchmark swing is ARC-AGI-2: 95% for GPT-6 Astra and 5.3% for Grok 4 Fast.

Side by side

GPT-6 AstraGrok 4 Fast
ProviderOpenAIxAI
Noometry Index70.839.4
Released2026-09-032025-09-19
WeightsProprietaryProprietary
Context window1.05M—
Max output128K—
Input $ / M tokens$10—
Output $ / M tokens$50—
Results tracked5630

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Category by category

Coding GPT-6 Astra leads

GPT-6 Astra: 73.7 (#2), Grok 4 Fast: 32.5 (#271)

BenchmarkGPT-6 AstraGrok 4 Fast
LMArena WebDev17861159
WeirdML93.6%42.9%
LMArena Coding14871429
DeepSWE74.1%—
FrontierCode53.3%—
FrontierSWE65.5%—
SciCode56.5%—
GSO79.4%—
MirrorCode46.7%—
ALE-Bench2,951—

Agentic & Tool Use GPT-6 Astra leads

GPT-6 Astra: 52.9 (#3), Grok 4 Fast: 29.5 (#86)

BenchmarkGPT-6 AstraGrok 4 Fast
APEX-Agents64.7%—
Remote Labor Index20.8%—
τ²-bench Banking—15.7%
Cybench—30%
BALROG68.3%—
GDP.pdf34.2%—
LMArena Search—1171
Vending-Bench 215,515—

Reasoning GPT-6 Astra leads

GPT-6 Astra: 85.1 (#1), Grok 4 Fast: 22.2 (#201)

BenchmarkGPT-6 AstraGrok 4 Fast
ARC-AGI-295%5.3%
ARC-AGI-198.5%48.5%
LMArena Hard Prompts14621412
DTBench97.3%82.7%
Epoch Capabilities Index166.45144.2
Kagi LLM Benchmark—66.1%
NYT Connections (extended)98.1%—
CritPt31.7%—
Chess Puzzles72%—
EBR-Bench76.2%—
Mystery Game Puzzles84%—
LMCA64.4%—
Bench to the Future 30.14—
ForecastBench—60.5

Math GPT-6 Astra leads

GPT-6 Astra: 93.5 (#2), Grok 4 Fast: 38.9 (#123)

BenchmarkGPT-6 AstraGrok 4 Fast
LMArena Math14651419
FrontierMath (Tiers 1-3)93.7%—
FrontierMath Tier 497.6%—
OTIS Mock AIME 2024-2025100%—
ProofBench99%—
FrontierMath Erdős2.9%—

Knowledge GPT-6 Astra leads

GPT-6 Astra: 75.3 (#1), Grok 4 Fast: 32.0 (#214)

BenchmarkGPT-6 AstraGrok 4 Fast
Vectara Hallucination Rate8.7%19.7%
LMArena Expert14831411
GPQA Diamond95.8%—
Humanity's Last Exam54.8%—
SimpleQA Verified75.6%—

Multimodal Not comparable

GPT-6 Astra: 55.0 (#3), Grok 4 Fast: —

BenchmarkGPT-6 AstraGrok 4 Fast
LMArena Vision1281—
Blueprint-Bench 249.7%—
Furniture Assembly80%—
LMArena Document1468—

Multilingual GPT-6 Astra leads

GPT-6 Astra: 53.7 (#61), Grok 4 Fast: 51.3 (#111)

BenchmarkGPT-6 AstraGrok 4 Fast
LMArena Non-English14301396
LMArena Chinese14841457
LMArena French14561431
LMArena German14401383
LMArena Japanese13791352
LMArena Korean14261357
LMArena Russian14361389
LMArena Spanish14071415

Instruction Following GPT-6 Astra leads

GPT-6 Astra: 76.3 (#44), Grok 4 Fast: 73.2 (#121)

BenchmarkGPT-6 AstraGrok 4 Fast
LMArena Instruction Following14501387

Long Context Grok 4 Fast leads

GPT-6 Astra: 44.5 (#62), Grok 4 Fast: 63.2 (#3)

BenchmarkGPT-6 AstraGrok 4 Fast
LMArena Longer Query14561415
Fiction.LiveBench—94.4%

Writing & Preference GPT-6 Astra leads

GPT-6 Astra: 75.3 (#7), Grok 4 Fast: 60.0 (#102)

BenchmarkGPT-6 AstraGrok 4 Fast
LMArena Text14411407
LMArena Creative Writing14181387
LMArena Multi-Turn14481414
EQ-Bench Creative Writing2173—

Frequently asked questions

Is GPT-6 Astra better than Grok 4 Fast?

GPT-6 Astra is the stronger model overall, scoring 70.8 to 39.4 on the Noometry Index.

Is GPT-6 Astra or Grok 4 Fast better for coding?

GPT-6 Astra scores higher on coding benchmarks: 73.7 versus 32.5 in the Noometry coding category.

How many benchmarks do GPT-6 Astra and Grok 4 Fast share?

24 benchmarks have published results for both models. GPT-6 Astra has 56 scored results on Noometry and Grok 4 Fast has 30.

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