Model comparison

Grok 4 Fast vs Phi-4 Mini

Grok 4 Fast is the stronger model overall, scoring 39.4 to 30.9 on the Noometry Index.

Last verified . 1 shared benchmarks.

Grok 4 Fast xAI

39.4

Rank #167 Confirmed

Phi-4 Mini Microsoft

30.9

Rank #283 Reported

Summary

  • They share 1 benchmark with published results for both. Grok 4 Fast scores higher in 2 categories and Phi-4 Mini in 1 category; 2 gaps are clear of the uncertainty.
  • The widest gap is in knowledge, where Grok 4 Fast leads 32.0 to 25.3.
  • Phi-4 Mini has downloadable open weights; the other is API-only.

Side by side

Grok 4 Fast and Phi-4 Mini specifications
Grok 4 FastPhi-4 Mini
ProviderxAIMicrosoft
Noometry Index39.430.9
Released2025-09-192024-12-11
WeightsProprietaryOpen
Context window—128K
Max output—4K
Input $ / M tokens—$0.075
Output $ / M tokens—$0.30
Results tracked303

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Category by category

Coding Grok 4 Fast leads

Grok 4 Fast: 32.5 (#271), Phi-4 Mini: 28.1 (#317)

Coding benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
LMArena WebDev1159—
SciCode—10.8%
WeirdML42.9%—
LMArena Coding1429—

Agentic & Tool Use Not comparable

Grok 4 Fast: 29.5 (#86), Phi-4 Mini: —

Agentic & Tool Use benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
τ²-bench Banking15.7%—
Cybench30%—
LMArena Search1171—

Reasoning Too close to call

Grok 4 Fast: 22.2 (#201), Phi-4 Mini: 22.4 (#195)

Reasoning benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
ARC-AGI-25.3%—
Kagi LLM Benchmark66.1%—
ARC-AGI-148.5%—
CritPt—0%
LMArena Hard Prompts1412—
DTBench82.7%—
Epoch Capabilities Index144.2—
ForecastBench60.5—

Math Not comparable

Grok 4 Fast: 38.9 (#123), Phi-4 Mini: —

Math benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
LMArena Math1419—

Knowledge Grok 4 Fast leads

Grok 4 Fast: 32.0 (#214), Phi-4 Mini: 25.3 (#262)

Knowledge benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
Vectara Hallucination Rate19.7%23.5%
LMArena Expert1411—

Multilingual Not comparable

Grok 4 Fast: 51.3 (#111), Phi-4 Mini: —

Multilingual benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
LMArena Non-English1396—
LMArena Chinese1457—
LMArena French1431—
LMArena German1383—
LMArena Japanese1352—
LMArena Korean1357—
LMArena Russian1389—
LMArena Spanish1415—

Instruction Following Not comparable

Grok 4 Fast: 73.2 (#121), Phi-4 Mini: —

Instruction Following benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
LMArena Instruction Following1387—

Long Context Not comparable

Grok 4 Fast: 63.2 (#3), Phi-4 Mini: —

Long Context benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
Fiction.LiveBench94.4%—
LMArena Longer Query1415—

Writing & Preference Not comparable

Grok 4 Fast: 60.0 (#102), Phi-4 Mini: —

Writing & Preference benchmarks
BenchmarkGrok 4 FastPhi-4 Mini
LMArena Text1407—
LMArena Creative Writing1387—
LMArena Multi-Turn1414—

Frequently asked questions

Is Grok 4 Fast better than Phi-4 Mini?

Grok 4 Fast is the stronger model overall, scoring 39.4 to 30.9 on the Noometry Index.

Is Grok 4 Fast or Phi-4 Mini better for coding?

Grok 4 Fast scores higher on coding benchmarks: 32.5 versus 28.1 in the Noometry coding category.

How many benchmarks do Grok 4 Fast and Phi-4 Mini share?

1 benchmark has published results for both models. Grok 4 Fast has 30 scored results on Noometry and Phi-4 Mini has 3.

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