Noometry

Model comparison

GPT-5.4 nano vs Grok 4 Fast

GPT-5.4 nano is the stronger model overall, scoring 41.9 to 39.0 on the Noometry Index.

Last verified . 25 shared benchmarks.

GPT-5.4 nano OpenAI

41.9

Rank #111 Confirmed

Grok 4 Fast xAI

39.0

Rank #164 Confirmed

Summary

  • They share 25 benchmarks with published results for both. GPT-5.4 nano scores higher in 4 categories and Grok 4 Fast in 4 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in long context, where Grok 4 Fast leads 63.2 to 41.6.
  • The biggest single-benchmark swing is Kagi LLM Benchmark: 39.7% for GPT-5.4 nano and 66.1% for Grok 4 Fast.

Side by side

GPT-5.4 nanoGrok 4 Fast
ProviderOpenAIxAI
Noometry Index41.939.0
Released2026-03-172025-09-19
WeightsProprietaryProprietary
Context window400K—
Max output128K—
Input $ / M tokens$0.20—
Output $ / M tokens$1.25—
Results tracked4030

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Category by category

Coding GPT-5.4 nano leads

GPT-5.4 nano: 43.1 (#82), Grok 4 Fast: 32.3 (#264)

BenchmarkGPT-5.4 nanoGrok 4 Fast
WeirdML49.2%42.9%
LMArena Coding14041429
LMArena WebDev—1160
SciCode46.9%—
ALE-Bench1,005—

Agentic & Tool Use Not comparable

GPT-5.4 nano: —, Grok 4 Fast: 29.3 (#80)

BenchmarkGPT-5.4 nanoGrok 4 Fast
τ²-bench Banking—15.7%
Cybench—30%
LMArena Search—1171

Reasoning GPT-5.4 nano leads

GPT-5.4 nano: 23.8 (#159), Grok 4 Fast: 22.5 (#179)

BenchmarkGPT-5.4 nanoGrok 4 Fast
ARC-AGI-25.7%5.3%
Kagi LLM Benchmark39.7%66.1%
ARC-AGI-151.5%48.5%
LMArena Hard Prompts13801413
DTBench80.3%82.7%
Epoch Capabilities Index145.78144.21
ForecastBench57.360.5
CritPt9.3%—
Chess Puzzles30%—
Mystery Game Puzzles9%—
LMCA36.9%—

Math GPT-5.4 nano leads

GPT-5.4 nano: 40.7 (#76), Grok 4 Fast: 36.1 (#126)

BenchmarkGPT-5.4 nanoGrok 4 Fast
LMArena Math14061419
FrontierMath (Tiers 1-3)44.9%—
FrontierMath Tier 412.2%—
OTIS Mock AIME 2024-202587.8%—
ProofBench5%—
FrontierMath (Feb 2025 set)25.9%—
FrontierMath Tier 4 (v1)6.3%—

Knowledge GPT-5.4 nano leads

GPT-5.4 nano: 41.8 (#94), Grok 4 Fast: 31.5 (#211)

BenchmarkGPT-5.4 nanoGrok 4 Fast
Vectara Hallucination Rate3.1%19.7%
LMArena Expert13971411
GPQA Diamond78.5%—
SimpleQA Verified11.7%—

Multimodal Not comparable

GPT-5.4 nano: 36.0 (#73), Grok 4 Fast: —

BenchmarkGPT-5.4 nanoGrok 4 Fast
LMArena Vision1196—

Multilingual Grok 4 Fast leads

GPT-5.4 nano: 48.8 (#136), Grok 4 Fast: 51.5 (#106)

BenchmarkGPT-5.4 nanoGrok 4 Fast
LMArena Non-English13591397
LMArena Chinese13911458
LMArena French13961433
LMArena German13681383
LMArena Japanese13421358
LMArena Korean13211359
LMArena Russian13631387
LMArena Spanish13681414

Instruction Following Grok 4 Fast leads

GPT-5.4 nano: 72.1 (#139), Grok 4 Fast: 73.4 (#116)

BenchmarkGPT-5.4 nanoGrok 4 Fast
LMArena Instruction Following13621388

Long Context Grok 4 Fast leads

GPT-5.4 nano: 41.6 (#131), Grok 4 Fast: 63.2 (#3)

BenchmarkGPT-5.4 nanoGrok 4 Fast
LMArena Longer Query13651415
Fiction.LiveBench—94.4%

Writing & Preference Grok 4 Fast leads

GPT-5.4 nano: 55.9 (#137), Grok 4 Fast: 60.2 (#96)

BenchmarkGPT-5.4 nanoGrok 4 Fast
LMArena Text13721407
LMArena Creative Writing13131388
LMArena Multi-Turn13821414

Frequently asked questions

Is GPT-5.4 nano better than Grok 4 Fast?

GPT-5.4 nano is the stronger model overall, scoring 41.9 to 39.0 on the Noometry Index.

Is GPT-5.4 nano or Grok 4 Fast better for coding?

GPT-5.4 nano scores higher on coding benchmarks: 43.1 versus 32.3 in the Noometry coding category.

How many benchmarks do GPT-5.4 nano and Grok 4 Fast share?

25 benchmarks have published results for both models. GPT-5.4 nano has 40 scored results on Noometry and Grok 4 Fast has 30.

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