Model comparison

GPT-5-Codex vs GPT-6 Sol

GPT-6 Sol is the stronger model overall, scoring 49.2 to 37.3 on the Noometry Index.

Last verified . 0 shared benchmarks.

GPT-5-Codex OpenAI

37.3

Rank #190 Reported

GPT-6 Sol OpenAI

49.2

Rank #46 Confirmed

Summary

  • The widest gap is in reasoning, where GPT-6 Sol leads 49.3 to 30.0.
  • GPT-5-Codex is cheaper at $1.25 / $10 per million input/output tokens, against $2 / $10 for GPT-6 Sol.
  • GPT-6 Sol accepts more context: 1.05M tokens versus 400K.

Side by side

GPT-5-Codex and GPT-6 Sol specifications
GPT-5-CodexGPT-6 Sol
ProviderOpenAIOpenAI
Noometry Index37.349.2
Released2025-09-152026-09-22
WeightsProprietaryProprietary
Context window400K1.05M
Max output128K128K
Input $ / M tokens$1.25$2
Output $ / M tokens$10$10
Results tracked322

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Category by category

Coding GPT-6 Sol leads

GPT-5-Codex: 41.9 (#100), GPT-6 Sol: 59.6 (#11)

Coding benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
DeepSWE—68.8%
FrontierCode—49.3%
LMArena WebDev—1692
WeirdML54.5%—
LMArena Coding—1453

Agentic & Tool Use GPT-6 Sol leads

GPT-5-Codex: 30.8 (#66), GPT-6 Sol: 33.5 (#49)

Agentic & Tool Use benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
Terminal-Bench44.3%—
GDP.pdf—28%

Reasoning GPT-6 Sol leads

GPT-5-Codex: 30.0 (#80), GPT-6 Sol: 49.3 (#34)

Reasoning benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
Kagi LLM Benchmark70.3%—
NYT Connections (extended)—90.1%
EBR-Bench—53.3%
LMArena Hard Prompts—1420

Math Not comparable

GPT-5-Codex: —, GPT-6 Sol: 35.8 (#135)

Math benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
LMArena Math—1404

Knowledge Not comparable

GPT-5-Codex: —, GPT-6 Sol: 43.0 (#87)

Knowledge benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
Vectara Hallucination Rate—6.5%
LMArena Expert—1449

Multimodal Not comparable

GPT-5-Codex: —, GPT-6 Sol: 47.6 (#9)

Multimodal benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
Furniture Assembly—58.3%

Multilingual Not comparable

GPT-5-Codex: —, GPT-6 Sol: 51.0 (#113)

Multilingual benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
LMArena Non-English—1389
LMArena Chinese—1416
LMArena Russian—1407
LMArena Spanish—1377

Instruction Following Not comparable

GPT-5-Codex: —, GPT-6 Sol: 74.4 (#97)

Instruction Following benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
LMArena Instruction Following—1406

Long Context Not comparable

GPT-5-Codex: —, GPT-6 Sol: 43.2 (#100)

Long Context benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
LMArena Longer Query—1415

Writing & Preference Not comparable

GPT-5-Codex: —, GPT-6 Sol: 72.3 (#15)

Writing & Preference benchmarks
BenchmarkGPT-5-CodexGPT-6 Sol
LMArena Text—1396
LMArena Creative Writing—1392
EQ-Bench Creative Writing—2125
LMArena Multi-Turn—1405

Frequently asked questions

Is GPT-5-Codex better than GPT-6 Sol?

GPT-6 Sol is the stronger model overall, scoring 49.2 to 37.3 on the Noometry Index.

Which is cheaper, GPT-5-Codex or GPT-6 Sol?

GPT-5-Codex is cheaper. It lists at $1.25 per million input tokens and $10 per million output tokens; GPT-6 Sol lists at $2 and $10.

Is GPT-5-Codex or GPT-6 Sol better for coding?

GPT-6 Sol scores higher on coding benchmarks: 59.6 versus 41.9 in the Noometry coding category.

Which has the bigger context window?

GPT-6 Sol does, with 1.05M tokens against 400K.

How many benchmarks do GPT-5-Codex and GPT-6 Sol share?

0 benchmarks have published results for both models. GPT-5-Codex has 3 scored results on Noometry and GPT-6 Sol has 22.

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