Model comparison

Granite 3.1 2b Instruct vs Grok 4.1 Fast

Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 33.2 on the Noometry Index.

Last verified . 12 shared benchmarks.

Granite 3.1 2b Instruct IBM

33.2

Rank #247 Confirmed

Grok 4.1 Fast xAI

41.4

Rank #136 Confirmed

Summary

  • They share 12 benchmarks with published results for both. Granite 3.1 2b Instruct scores higher in 1 category and Grok 4.1 Fast in 7 categories; 7 gaps are clear of the uncertainty.
  • The widest gap is in writing & preference, where Grok 4.1 Fast leads 57.2 to 34.1.
  • Granite 3.1 2b Instruct has downloadable open weights; the other is API-only.

Side by side

Granite 3.1 2b Instruct and Grok 4.1 Fast specifications
Granite 3.1 2b InstructGrok 4.1 Fast
ProviderIBMxAI
Noometry Index33.241.4
Released—2025-06-27
WeightsOpenProprietary
Context window—128K
Max output—30K
Input $ / M tokens—$0.20
Output $ / M tokens—$0.50
Results tracked1232

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Category by category

Coding Too close to call

Granite 3.1 2b Instruct: 33.4 (#257), Grok 4.1 Fast: 34.1 (#245)

Coding benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Coding11491411
LMArena WebDev—1242
ALE-Bench—394.93

Agentic & Tool Use Not comparable

Granite 3.1 2b Instruct: —, Grok 4.1 Fast: 36.3 (#39)

Agentic & Tool Use benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
Berkeley Function Calling Leaderboard—69.6%
τ²-bench Banking—13.1%
LMArena Search—1171
Vending-Bench 2—1,107

Reasoning Grok 4.1 Fast leads

Granite 3.1 2b Instruct: 22.0 (#209), Grok 4.1 Fast: 43.4 (#49)

Reasoning benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Hard Prompts11381407
SimpleBench—56%
NYT Connections (extended)—87.4%
DTBench—87.7%
ForecastBench—61

Math Granite 3.1 2b Instruct leads

Granite 3.1 2b Instruct: 33.1 (#206), Grok 4.1 Fast: 31.9 (#221)

Math benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Math11591408
MathArena Final-Answer Competitions—60.9%
ProofBench—4%

Knowledge Grok 4.1 Fast leads

Granite 3.1 2b Instruct: 30.8 (#224), Grok 4.1 Fast: 33.1 (#207)

Knowledge benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Expert11311399
Vectara Hallucination Rate—17.8%

Multimodal Not comparable

Granite 3.1 2b Instruct: —, Grok 4.1 Fast: 37.0 (#76)

Multimodal benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Vision—1201

Multilingual Grok 4.1 Fast leads

Granite 3.1 2b Instruct: 29.1 (#269), Grok 4.1 Fast: 51.0 (#114)

Multilingual benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Non-English10681391
LMArena Chinese11391441
LMArena Russian10631387
LMArena French—1415
LMArena German—1404
LMArena Japanese—1349
LMArena Korean—1361
LMArena Spanish—1413

Instruction Following Grok 4.1 Fast leads

Granite 3.1 2b Instruct: 57.7 (#264), Grok 4.1 Fast: 72.7 (#133)

Instruction Following benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Instruction Following11161376

Long Context Grok 4.1 Fast leads

Granite 3.1 2b Instruct: 35.0 (#244), Grok 4.1 Fast: 42.4 (#126)

Long Context benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Longer Query11551390

Writing & Preference Grok 4.1 Fast leads

Granite 3.1 2b Instruct: 34.1 (#274), Grok 4.1 Fast: 57.2 (#131)

Writing & Preference benchmarks
BenchmarkGranite 3.1 2b InstructGrok 4.1 Fast
LMArena Text11271408
LMArena Creative Writing11161394
LMArena Multi-Turn10991389
EQ-Bench Creative Writing—1327

Frequently asked questions

Is Granite 3.1 2b Instruct better than Grok 4.1 Fast?

Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 33.2 on the Noometry Index.

Is Granite 3.1 2b Instruct or Grok 4.1 Fast better for coding?

They score almost the same on coding (33.4 vs 34.1); test both on your own repository before choosing.

How many benchmarks do Granite 3.1 2b Instruct and Grok 4.1 Fast share?

12 benchmarks have published results for both models. Granite 3.1 2b Instruct has 12 scored results on Noometry and Grok 4.1 Fast has 32.

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