Model comparison

GPT-5-Codex vs Grok 4

Grok 4 is the stronger model overall, scoring 48.1 to 37.9 on the Noometry Index.

Last verified . 3 shared benchmarks.

GPT-5-Codex OpenAI

37.9

Rank #192 Reported

Grok 4 xAI

48.1

Rank #56 Confirmed

Summary

  • They share 3 benchmarks with published results for both. GPT-5-Codex scores higher in 0 categories and Grok 4 in 3 categories; 3 gaps are clear of the uncertainty.
  • The widest gap is in coding, where Grok 4 leads 50.3 to 42.4.
  • The biggest single-benchmark swing is Terminal-Bench: 44.3% for GPT-5-Codex and 27.2% for Grok 4.

Side by side

GPT-5-Codex and Grok 4 specifications
GPT-5-CodexGrok 4
ProviderOpenAIxAI
Noometry Index37.948.1
Released2025-09-152025-07-09
WeightsProprietaryProprietary
Context window400K—
Max output128K—
Input $ / M tokens$1.25—
Output $ / M tokens$10—
Results tracked348

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Category by category

Coding Grok 4 leads

GPT-5-Codex: 42.4 (#103), Grok 4: 50.3 (#46)

Coding benchmarks
BenchmarkGPT-5-CodexGrok 4
WeirdML54.5%45.7%
Aider Polyglot—79.6%
LMArena Coding—1408

Agentic & Tool Use Grok 4 leads

GPT-5-Codex: 31.0 (#72), Grok 4: 32.3 (#68)

Agentic & Tool Use benchmarks
BenchmarkGPT-5-CodexGrok 4
Terminal-Bench44.3%27.2%
Berkeley Function Calling Leaderboard—63%
GDPval—21.1%
Cybench—43%
DeepResearch Bench—47.3%
BALROG—43.6%
LMArena Search—1142
METR Time Horizons—66.6%

Reasoning Grok 4 leads

GPT-5-Codex: 30.9 (#83), Grok 4: 36.7 (#65)

Reasoning benchmarks
BenchmarkGPT-5-CodexGrok 4
Kagi LLM Benchmark70.3%73.6%
ARC-AGI-2—16%
SimpleBench—60.5%
ARC-AGI-1—66.7%
Chess Puzzles—28%
LMArena Hard Prompts—1409
Epoch Capabilities Index—146.44
ForecastBench—60.9

Math Not comparable

GPT-5-Codex: —, Grok 4: 48.4 (#64)

Math benchmarks
BenchmarkGPT-5-CodexGrok 4
OTIS Mock AIME 2024-2025—84%
Omni-MATH—60.3%
LMArena Math—1422
FrontierMath (Feb 2025 set)—19.7%
FrontierMath Tier 4 (v1)—2.1%

Knowledge Not comparable

GPT-5-Codex: —, Grok 4: 53.8 (#55)

Knowledge benchmarks
BenchmarkGPT-5-CodexGrok 4
GPQA Diamond—87%
MMLU-Pro—85.1%
Confabulations—12.4%
GPQA (HELM)—72.7%
LMArena Expert—1415

Multimodal Not comparable

GPT-5-Codex: —, Grok 4: 33.7 (#94)

Multimodal benchmarks
BenchmarkGPT-5-CodexGrok 4
LMArena Vision—1210
GeoBench—45%

Multilingual Not comparable

GPT-5-Codex: —, Grok 4: 51.8 (#103)

Multilingual benchmarks
BenchmarkGPT-5-CodexGrok 4
LMArena Non-English—1403
LMArena Chinese—1427
LMArena French—1418
LMArena German—1429
LMArena Japanese—1394
LMArena Korean—1377
LMArena Russian—1410
LMArena Spanish—1420

Instruction Following Not comparable

GPT-5-Codex: —, Grok 4: 79.2 (#5)

Instruction Following benchmarks
BenchmarkGPT-5-CodexGrok 4
IFEval—94.9%
LMArena Instruction Following—1387

Long Context Not comparable

GPT-5-Codex: —, Grok 4: 63.1 (#4)

Long Context benchmarks
BenchmarkGPT-5-CodexGrok 4
Fiction.LiveBench—94.4%
LMArena Longer Query—1409

Writing & Preference Not comparable

GPT-5-Codex: —, Grok 4: 58.5 (#116)

Writing & Preference benchmarks
BenchmarkGPT-5-CodexGrok 4
LMArena Text—1411
LMArena Creative Writing—1397
Short-Story Creative Writing—76.9%
WildBench—79.7%
LMArena Multi-Turn—1416

Frequently asked questions

Is GPT-5-Codex better than Grok 4?

Grok 4 is the stronger model overall, scoring 48.1 to 37.9 on the Noometry Index.

Is GPT-5-Codex or Grok 4 better for coding?

Grok 4 scores higher on coding benchmarks: 50.3 versus 42.4 in the Noometry coding category.

How many benchmarks do GPT-5-Codex and Grok 4 share?

3 benchmarks have published results for both models. GPT-5-Codex has 3 scored results on Noometry and Grok 4 has 48.

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