Noometry

Model comparison

Grok 4.5 vs Step 3

Grok 4.5 is the stronger model overall, scoring 55.0 to 40.5 on the Noometry Index.

Last verified . 17 shared benchmarks.

Grok 4.5 xAI

55.0

Rank #25 Confirmed

Step 3 StepFun

40.5

Rank #149 Confirmed

Summary

  • They share 17 benchmarks with published results for both. Grok 4.5 scores higher in 9 categories and Step 3 in 0 categories; 9 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Grok 4.5 leads 56.1 to 28.4.
  • The biggest single-benchmark swing is Kagi LLM Benchmark: 83.5% for Grok 4.5 and 62.3% for Step 3.
  • Step 3 has downloadable open weights; the other is API-only.

Side by side

Grok 4.5Step 3
ProviderxAIStepFun
Noometry Index55.040.5
Released2026-07-08—
WeightsProprietaryOpen
Context window500K—
Max output500K—
Input $ / M tokens$2—
Output $ / M tokens$6—
Results tracked5217

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Category by category

Coding Grok 4.5 leads

Grok 4.5: 52.2 (#35), Step 3: 40.1 (#147)

BenchmarkGrok 4.5Step 3
LMArena Coding14741367
DeepSWE53.8%—
FrontierCode42.4%—
LMArena WebDev1553—
SciCode54.1%—
WeirdML46.4%—
ALE-Bench1,309—

Agentic & Tool Use Not comparable

Grok 4.5: 44.4 (#17), Step 3: —

BenchmarkGrok 4.5Step 3
APEX-Agents56.2%—
τ²-bench Banking47.9%—
PostTrainBench23.4%—
GBAEval65.4%—
GDP.pdf14%—
LMArena Search1213—
Vending-Bench 23,887—

Reasoning Grok 4.5 leads

Grok 4.5: 56.1 (#25), Step 3: 28.4 (#105)

BenchmarkGrok 4.5Step 3
Kagi LLM Benchmark83.5%62.3%
LMArena Hard Prompts14621355
ARC-AGI-252.6%—
SimpleBench70%—
NYT Connections (extended)79.9%—
ARC-AGI-187.2%—
CritPt15.4%—
Chess Puzzles36%—
DTBench96.5%—
LMCA45.2%—
Surface Evolver Bench74.4%—
Epoch Capabilities Index153.92—

Math Grok 4.5 leads

Grok 4.5: 60.9 (#35), Step 3: 37.6 (#148)

BenchmarkGrok 4.5Step 3
LMArena Math14591366
FrontierMath (Tiers 1-3)57.2%—
FrontierMath Tier 424.4%—
OTIS Mock AIME 2024-202597.8%—
ProofBench31%—

Knowledge Grok 4.5 leads

Grok 4.5: 62.3 (#24), Step 3: 36.8 (#164)

BenchmarkGrok 4.5Step 3
LMArena Expert14661333
GPQA Diamond93.4%—
SimpleQA Verified48.3%—

Multimodal Grok 4.5 leads

Grok 4.5: 37.6 (#72), Step 3: 35.5 (#86)

BenchmarkGrok 4.5Step 3
LMArena Vision12881177
Blueprint-Bench 227.3%—
Furniture Assembly22.5%—
LMArena Document1452—

Multilingual Grok 4.5 leads

Grok 4.5: 54.4 (#42), Step 3: 46.3 (#159)

BenchmarkGrok 4.5Step 3
LMArena Non-English14401327
LMArena Chinese14961397
LMArena German14461371
LMArena Korean14041269
LMArena Russian14481331
LMArena Spanish14501371
LMArena French1456—
LMArena Japanese1428—

Instruction Following Grok 4.5 leads

Grok 4.5: 76.0 (#48), Step 3: 70.4 (#164)

BenchmarkGrok 4.5Step 3
LMArena Instruction Following14461332

Long Context Grok 4.5 leads

Grok 4.5: 44.8 (#56), Step 3: 40.3 (#157)

BenchmarkGrok 4.5Step 3
LMArena Longer Query14631326

Writing & Preference Grok 4.5 leads

Grok 4.5: 65.8 (#42), Step 3: 54.3 (#151)

BenchmarkGrok 4.5Step 3
LMArena Text14481350
LMArena Creative Writing14421321
LMArena Multi-Turn14561341
EQ-Bench Creative Writing1579—

Frequently asked questions

Is Grok 4.5 better than Step 3?

Grok 4.5 is the stronger model overall, scoring 55.0 to 40.5 on the Noometry Index.

Is Grok 4.5 or Step 3 better for coding?

Grok 4.5 scores higher on coding benchmarks: 52.2 versus 40.1 in the Noometry coding category.

How many benchmarks do Grok 4.5 and Step 3 share?

17 benchmarks have published results for both models. Grok 4.5 has 52 scored results on Noometry and Step 3 has 17.

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