Model comparison

GPT-5 Pro vs Grok 4.5

Grok 4.5 is the stronger model overall, scoring 55.0 to 46.4 on the Noometry Index.

Last verified . 8 shared benchmarks.

GPT-5 Pro OpenAI

46.4

Rank #64 Confirmed

Grok 4.5 xAI

55.0

Rank #25 Confirmed

Summary

  • They share 8 benchmarks with published results for both. GPT-5 Pro scores higher in 0 categories and Grok 4.5 in 4 categories; 4 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Grok 4.5 leads 56.1 to 38.9.
  • The biggest single-benchmark swing is ARC-AGI-2: 18.3% for GPT-5 Pro and 52.6% for Grok 4.5.
  • Grok 4.5 is cheaper at $2 / $6 per million input/output tokens, against $15 / $120 for GPT-5 Pro.
  • Grok 4.5 accepts more context: 500K tokens versus 400K.

Side by side

GPT-5 Pro and Grok 4.5 specifications
GPT-5 ProGrok 4.5
ProviderOpenAIxAI
Noometry Index46.455.0
Released2025-10-062026-07-08
WeightsProprietaryProprietary
Context window400K500K
Max output272K500K
Input $ / M tokens$15$2
Output $ / M tokens$120$6
Results tracked1252

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

Category by category

Coding Grok 4.5 leads

GPT-5 Pro: 44.0 (#80), Grok 4.5: 52.2 (#35)

Coding benchmarks
BenchmarkGPT-5 ProGrok 4.5
WeirdML60.4%46.4%
DeepSWE—53.8%
FrontierCode—42.4%
LMArena WebDev—1553
SciCode—54.1%
LMArena Coding—1474
ALE-Bench—1,309
AlgoTune1.31—

Agentic & Tool Use Not comparable

GPT-5 Pro: —, Grok 4.5: 44.4 (#17)

Agentic & Tool Use benchmarks
BenchmarkGPT-5 ProGrok 4.5
APEX-Agents—56.2%
τ²-bench Banking—47.9%
PostTrainBench—23.4%
GBAEval—65.4%
GDP.pdf—14%
LMArena Search—1213
Vending-Bench 2—3,887

Reasoning Grok 4.5 leads

GPT-5 Pro: 38.9 (#62), Grok 4.5: 56.1 (#25)

Reasoning benchmarks
BenchmarkGPT-5 ProGrok 4.5
ARC-AGI-218.3%52.6%
SimpleBench61.6%70%
Kagi LLM Benchmark76.8%83.5%
ARC-AGI-170.2%87.2%
Epoch Capabilities Index150.28153.92
NYT Connections (extended)—79.9%
CritPt—15.4%
Chess Puzzles—36%
EnigmaEval18.8%—
LMArena Hard Prompts—1462
DTBench—96.5%
LMCA—45.2%
Surface Evolver Bench—74.4%

Math Grok 4.5 leads

GPT-5 Pro: 48.5 (#63), Grok 4.5: 60.9 (#35)

Math benchmarks
BenchmarkGPT-5 ProGrok 4.5
FrontierMath (Tiers 1-3)55.8%57.2%
FrontierMath Tier 419.5%24.4%
OTIS Mock AIME 2024-2025—97.8%
ProofBench—31%
LMArena Math—1459
FrontierMath Tier 4 (v1)14.6%—

Knowledge Grok 4.5 leads

GPT-5 Pro: 56.7 (#42), Grok 4.5: 62.3 (#24)

Knowledge benchmarks
BenchmarkGPT-5 ProGrok 4.5
GPQA Diamond—93.4%
Humanity's Last Exam31.6%—
SimpleQA Verified—48.3%
LMArena Expert—1466

Multimodal Not comparable

GPT-5 Pro: —, Grok 4.5: 37.6 (#72)

Multimodal benchmarks
BenchmarkGPT-5 ProGrok 4.5
LMArena Vision—1288
Blueprint-Bench 2—27.3%
Furniture Assembly—22.5%
LMArena Document—1452

Multilingual Not comparable

GPT-5 Pro: —, Grok 4.5: 54.4 (#42)

Multilingual benchmarks
BenchmarkGPT-5 ProGrok 4.5
LMArena Non-English—1440
LMArena Chinese—1496
LMArena French—1456
LMArena German—1446
LMArena Japanese—1428
LMArena Korean—1404
LMArena Russian—1448
LMArena Spanish—1450

Instruction Following Not comparable

GPT-5 Pro: —, Grok 4.5: 76.0 (#48)

Instruction Following benchmarks
BenchmarkGPT-5 ProGrok 4.5
LMArena Instruction Following—1446

Long Context Not comparable

GPT-5 Pro: —, Grok 4.5: 44.8 (#56)

Long Context benchmarks
BenchmarkGPT-5 ProGrok 4.5
LMArena Longer Query—1463

Writing & Preference Not comparable

GPT-5 Pro: —, Grok 4.5: 65.8 (#42)

Writing & Preference benchmarks
BenchmarkGPT-5 ProGrok 4.5
LMArena Text—1448
LMArena Creative Writing—1442
EQ-Bench Creative Writing—1579
LMArena Multi-Turn—1456

Frequently asked questions

Is GPT-5 Pro better than Grok 4.5?

Grok 4.5 is the stronger model overall, scoring 55.0 to 46.4 on the Noometry Index.

Which is cheaper, GPT-5 Pro or Grok 4.5?

Grok 4.5 is cheaper. It lists at $2 per million input tokens and $6 per million output tokens; GPT-5 Pro lists at $15 and $120.

Is GPT-5 Pro or Grok 4.5 better for coding?

Grok 4.5 scores higher on coding benchmarks: 52.2 versus 44.0 in the Noometry coding category.

Which has the bigger context window?

Grok 4.5 does, with 500K tokens against 400K.

How many benchmarks do GPT-5 Pro and Grok 4.5 share?

8 benchmarks have published results for both models. GPT-5 Pro has 12 scored results on Noometry and Grok 4.5 has 52.

Related comparisons

Go deeper