Noometry

Model comparison

GPT-5.2 Codex vs o1

GPT-5.2 Codex is the stronger model overall, scoring 42.2 to 40.6 on the Noometry Index.

Last verified . 0 shared benchmarks.

GPT-5.2 Codex OpenAI

42.2

Rank #107 Reported

o1 OpenAI

40.6

Rank #140 Confirmed

Summary

  • The widest gap is in agentic & tool use, where GPT-5.2 Codex leads 40.7 to 24.3.
  • GPT-5.2 Codex is cheaper at $1.75 / $14 per million input/output tokens, against $15 / $60 for o1.
  • GPT-5.2 Codex accepts more context: 400K tokens versus 200K.

Side by side

GPT-5.2 Codexo1
ProviderOpenAIOpenAI
Noometry Index42.240.6
Released2025-12-182024-09-12
WeightsProprietaryProprietary
Context window400K200K
Max output128K100K
Input $ / M tokens$1.75$15
Output $ / M tokens$14$60
Results tracked552

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Category by category

Coding Too close to call

GPT-5.2 Codex: 45.4 (#66), o1: 45.7 (#64)

BenchmarkGPT-5.2 Codexo1
SWE-bench Verified (bash only)72.8%—
Aider Polyglot—61.7%
LMArena WebDev1339—
SWE-bench Multilingual66.3%—
WeirdML—47.6%
LiveBench Coding—69.7%
LMArena Coding—1367
CadEval—56%
ALE-Bench1,300—
HumanEval+—89%
MBPP+—80.2%

Agentic & Tool Use GPT-5.2 Codex leads

GPT-5.2 Codex: 40.7 (#20), o1: 24.3 (#111)

BenchmarkGPT-5.2 Codexo1
Terminal-Bench66.5%—
Cybench—10%
METR Time Horizons—51.1%

Reasoning Not comparable

GPT-5.2 Codex: —, o1: 27.5 (#103)

BenchmarkGPT-5.2 Codexo1
SimpleBench—41.7%
ARC-AGI-1—30.7%
Chess Puzzles—15%
EnigmaEval—5.7%
LiveBench Reasoning—91.6%
LMArena Hard Prompts—1372
DTBench—74.7%
LiveBench Data Analysis—65.5%
LMCA—22.3%
Epoch Capabilities Index—141.92
LiveBench—75.7%

Math Not comparable

GPT-5.2 Codex: —, o1: 34.9 (#150)

BenchmarkGPT-5.2 Codexo1
FrontierMath (Tiers 1-3)—14.7%
OTIS Mock AIME 2024-2025—73.3%
LiveBench Math—80.3%
LMArena Math—1388
MATH Level 5—94.7%
FrontierMath (Feb 2025 set)—9.3%

Knowledge Not comparable

GPT-5.2 Codex: —, o1: 41.5 (#101)

BenchmarkGPT-5.2 Codexo1
GPQA Diamond—76.8%
Humanity's Last Exam—8%
SimpleQA Verified—41.1%
Confabulations—11.7%
LMArena Expert—1362

Multimodal Not comparable

GPT-5.2 Codex: —, o1: 33.6 (#87)

BenchmarkGPT-5.2 Codexo1
LMArena Vision—1168
GeoBench—80%
VPCT—37%
SpatialViz-Bench—41.4%

Multilingual Not comparable

GPT-5.2 Codex: —, o1: 48.8 (#137)

BenchmarkGPT-5.2 Codexo1
LMArena Non-English—1359
LMArena Chinese—1394
LMArena French—1343
LMArena German—1337
LMArena Japanese—1346
LMArena Korean—1396
LMArena Russian—1356
LMArena Spanish—1345

Instruction Following Not comparable

GPT-5.2 Codex: —, o1: 75.0 (#82)

BenchmarkGPT-5.2 Codexo1
LiveBench Instruction Following—81.5%
LMArena Instruction Following—1368

Long Context Not comparable

GPT-5.2 Codex: —, o1: 50.3 (#9)

BenchmarkGPT-5.2 Codexo1
Fiction.LiveBench—83.3%
LMArena Longer Query—1378

Writing & Preference Not comparable

GPT-5.2 Codex: —, o1: 55.8 (#139)

BenchmarkGPT-5.2 Codexo1
LMArena Text—1366
LMArena Creative Writing—1347
Short-Story Creative Writing—70.2%
LMArena Multi-Turn—1368
LiveBench Language—65.4%

Frequently asked questions

Is GPT-5.2 Codex better than o1?

GPT-5.2 Codex is the stronger model overall, scoring 42.2 to 40.6 on the Noometry Index.

Which is cheaper, GPT-5.2 Codex or o1?

GPT-5.2 Codex is cheaper. It lists at $1.75 per million input tokens and $14 per million output tokens; o1 lists at $15 and $60.

Is GPT-5.2 Codex or o1 better for coding?

They score almost the same on coding (45.4 vs 45.7); test both on your own repository before choosing.

Which has the bigger context window?

GPT-5.2 Codex does, with 400K tokens against 200K.

How many benchmarks do GPT-5.2 Codex and o1 share?

0 benchmarks have published results for both models. GPT-5.2 Codex has 5 scored results on Noometry and o1 has 52.

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