Noometry

Model comparison

GPT-6.1 Sol vs Grok 4 Fast

GPT-6.1 Sol is the stronger model overall, scoring 65.6 to 39.4 on the Noometry Index.

Last verified . 16 shared benchmarks.

GPT-6.1 Sol OpenAI

65.6

Rank #6 Confirmed

Grok 4 Fast xAI

39.4

Rank #167 Confirmed

Summary

  • They share 16 benchmarks with published results for both. GPT-6.1 Sol 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-6.1 Sol leads 81.9 to 22.2.
  • The biggest single-benchmark swing is ARC-AGI-2: 94.2% for GPT-6.1 Sol and 5.3% for Grok 4 Fast.

Side by side

GPT-6.1 SolGrok 4 Fast
ProviderOpenAIxAI
Noometry Index65.639.4
Released2026-09-292025-09-19
WeightsProprietaryProprietary
Context window1.05M—
Max output128K—
Input $ / M tokens$2—
Output $ / M tokens$10—
Results tracked3430

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

Category by category

Coding GPT-6.1 Sol leads

GPT-6.1 Sol: 63.2 (#8), Grok 4 Fast: 32.5 (#271)

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena WebDev17551159
LMArena Coding14871429
DeepSWE75.2%—
FrontierCode50.2%—
SciCode55.8%—
WeirdML—42.9%

Agentic & Tool Use GPT-6.1 Sol leads

GPT-6.1 Sol: 39.6 (#26), Grok 4 Fast: 29.5 (#86)

BenchmarkGPT-6.1 SolGrok 4 Fast
APEX-Agents60%—
τ²-bench Banking—15.7%
Cybench—30%
GDP.pdf32%—
LMArena Search—1171

Reasoning GPT-6.1 Sol leads

GPT-6.1 Sol: 81.9 (#2), Grok 4 Fast: 22.2 (#201)

BenchmarkGPT-6.1 SolGrok 4 Fast
ARC-AGI-294.2%5.3%
ARC-AGI-198.5%48.5%
LMArena Hard Prompts14661412
Epoch Capabilities Index166.09144.2
Kagi LLM Benchmark—66.1%
NYT Connections (extended)95.5%—
CritPt31.7%—
Chess Puzzles61%—
EBR-Bench54.3%—
Mystery Game Puzzles80%—
DTBench—82.7%
ForecastBench—60.5

Math GPT-6.1 Sol leads

GPT-6.1 Sol: 93.7 (#1), Grok 4 Fast: 38.9 (#123)

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena Math14641419
FrontierMath (Tiers 1-3)93.7%—
FrontierMath Tier 4100%—
OTIS Mock AIME 2024-2025100%—
ProofBench99%—

Knowledge GPT-6.1 Sol leads

GPT-6.1 Sol: 71.8 (#4), Grok 4 Fast: 32.0 (#214)

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena Expert15021411
GPQA Diamond95.4%—
SimpleQA Verified73.9%—
Vectara Hallucination Rate—19.7%

Multimodal Not comparable

GPT-6.1 Sol: 52.7 (#5), Grok 4 Fast: —

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena Vision1288—
Furniture Assembly80%—

Multilingual GPT-6.1 Sol leads

GPT-6.1 Sol: 54.3 (#46), Grok 4 Fast: 51.3 (#111)

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena Non-English14381396
LMArena Chinese14771457
LMArena Russian14551389
LMArena French—1431
LMArena German—1383
LMArena Japanese—1352
LMArena Korean—1357
LMArena Spanish—1415

Instruction Following GPT-6.1 Sol leads

GPT-6.1 Sol: 77.0 (#29), Grok 4 Fast: 73.2 (#121)

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena Instruction Following14681387

Long Context Grok 4 Fast leads

GPT-6.1 Sol: 44.9 (#54), Grok 4 Fast: 63.2 (#3)

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena Longer Query14651415
Fiction.LiveBench—94.4%

Writing & Preference GPT-6.1 Sol leads

GPT-6.1 Sol: 63.6 (#63), Grok 4 Fast: 60.0 (#102)

BenchmarkGPT-6.1 SolGrok 4 Fast
LMArena Text14471407
LMArena Creative Writing14321387
LMArena Multi-Turn14491414

Frequently asked questions

Is GPT-6.1 Sol better than Grok 4 Fast?

GPT-6.1 Sol is the stronger model overall, scoring 65.6 to 39.4 on the Noometry Index.

Is GPT-6.1 Sol or Grok 4 Fast better for coding?

GPT-6.1 Sol scores higher on coding benchmarks: 63.2 versus 32.5 in the Noometry coding category.

How many benchmarks do GPT-6.1 Sol and Grok 4 Fast share?

16 benchmarks have published results for both models. GPT-6.1 Sol has 34 scored results on Noometry and Grok 4 Fast has 30.

Related comparisons

Go deeper