Model comparison

GPT-5-Codex vs Grok-2 (Dec 2024)

GPT-5-Codex is the stronger model overall, scoring 37.9 to 33.7 on the Noometry Index.

Last verified . 1 shared benchmarks.

GPT-5-Codex OpenAI

37.9

Rank #192 Reported

Grok-2 (Dec 2024) xAI

33.7

Rank #239 Confirmed

Summary

  • They share 1 benchmark with published results for both. GPT-5-Codex scores higher in 2 categories and Grok-2 (Dec 2024) in 0 categories; 2 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where GPT-5-Codex leads 30.9 to 16.9.
  • The biggest single-benchmark swing is WeirdML: 54.5% for GPT-5-Codex and 22.2% for Grok-2 (Dec 2024).

Side by side

GPT-5-Codex and Grok-2 (Dec 2024) specifications
GPT-5-CodexGrok-2 (Dec 2024)
ProviderOpenAIxAI
Noometry Index37.933.7
Released2025-09-152024-08-13
WeightsProprietaryProprietary
Context window400K—
Max output128K—
Input $ / M tokens$1.25—
Output $ / M tokens$10—
Results tracked334

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Category by category

Coding GPT-5-Codex leads

GPT-5-Codex: 42.4 (#103), Grok-2 (Dec 2024): 33.3 (#258)

Coding benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
WeirdML54.5%22.2%
LiveBench Coding—46.4%
LMArena Coding—1287

Agentic & Tool Use Not comparable

GPT-5-Codex: 31.0 (#72), Grok-2 (Dec 2024): —

Agentic & Tool Use benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
Terminal-Bench44.3%—

Reasoning GPT-5-Codex leads

GPT-5-Codex: 30.9 (#83), Grok-2 (Dec 2024): 16.9 (#299)

Reasoning benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
SimpleBench—22.7%
Kagi LLM Benchmark70.3%—
LiveBench Reasoning—54.8%
LMArena Hard Prompts—1272
DTBench—65.2%
LiveBench Data Analysis—54.5%
Epoch Capabilities Index—130.48
LiveBench—54.3%

Math Not comparable

GPT-5-Codex: —, Grok-2 (Dec 2024): 20.8 (#284)

Math benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
OTIS Mock AIME 2024-2025—11.5%
LiveBench Math—54.9%
LMArena Math—1283
MATH Level 5—63.5%
FrontierMath (Feb 2025 set)—0.7%

Knowledge Not comparable

GPT-5-Codex: —, Grok-2 (Dec 2024): 29.8 (#233)

Knowledge benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
GPQA Diamond—53.8%
Confabulations—20.1%
LMArena Expert—1254

Multilingual Not comparable

GPT-5-Codex: —, Grok-2 (Dec 2024): 43.1 (#188)

Multilingual benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
LMArena Non-English—1282
LMArena Chinese—1289
LMArena French—1318
LMArena German—1287
LMArena Japanese—1244
LMArena Korean—1237
LMArena Russian—1286
LMArena Spanish—1281

Instruction Following Not comparable

GPT-5-Codex: —, Grok-2 (Dec 2024): 66.9 (#202)

Instruction Following benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
LiveBench Instruction Following—69.6%
LMArena Instruction Following—1270

Long Context Not comparable

GPT-5-Codex: —, Grok-2 (Dec 2024): 38.8 (#190)

Long Context benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
LMArena Longer Query—1276

Writing & Preference Not comparable

GPT-5-Codex: —, Grok-2 (Dec 2024): 48.6 (#198)

Writing & Preference benchmarks
BenchmarkGPT-5-CodexGrok-2 (Dec 2024)
LMArena Text—1305
LMArena Creative Writing—1284
Short-Story Creative Writing—63.6%
LMArena Multi-Turn—1290
LiveBench Language—45.6%

Frequently asked questions

Is GPT-5-Codex better than Grok-2 (Dec 2024)?

GPT-5-Codex is the stronger model overall, scoring 37.9 to 33.7 on the Noometry Index.

Is GPT-5-Codex or Grok-2 (Dec 2024) better for coding?

GPT-5-Codex scores higher on coding benchmarks: 42.4 versus 33.3 in the Noometry coding category.

How many benchmarks do GPT-5-Codex and Grok-2 (Dec 2024) share?

1 benchmark has published results for both models. GPT-5-Codex has 3 scored results on Noometry and Grok-2 (Dec 2024) has 34.

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