Model comparison

GPT-5-Codex vs Qwen3.5-9B

GPT-5-Codex is the stronger model overall, scoring 37.3 to 33.3 on the Noometry Index. Qwen3.5-9B costs 31× less per token, which makes it the better buy when GPT-5-Codex's lead doesn't matter for your workload.

Last verified . 1 shared benchmarks.

GPT-5-Codex OpenAI

37.3

Rank #190 Reported

Qwen3.5-9B Alibaba (Qwen)

33.3

Rank #235 Confirmed

Summary

  • They share 1 benchmark with published results for both. GPT-5-Codex scores higher in 3 categories and Qwen3.5-9B in 0 categories; 3 gaps are clear of the uncertainty.
  • The widest gap is in agentic & tool use, where GPT-5-Codex leads 30.8 to 14.4.
  • The biggest single-benchmark swing is Terminal-Bench: 44.3% for GPT-5-Codex and 9.2% for Qwen3.5-9B.
  • Qwen3.5-9B is cheaper at $0.10 / $0.15 per million input/output tokens, against $1.25 / $10 for GPT-5-Codex.
  • GPT-5-Codex accepts more context: 400K tokens versus 262K.
  • Qwen3.5-9B has downloadable open weights; the other is API-only.

Side by side

GPT-5-Codex and Qwen3.5-9B specifications
GPT-5-CodexQwen3.5-9B
ProviderOpenAIAlibaba (Qwen)
Noometry Index37.333.3
Released2025-09-152026-02-23
WeightsProprietaryOpen
Context window400K262K
Max output128K66K
Input $ / M tokens$1.25$0.10
Output $ / M tokens$10$0.15
Results tracked310

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Category by category

Coding GPT-5-Codex leads

GPT-5-Codex: 41.9 (#100), Qwen3.5-9B: 35.3 (#213)

Coding benchmarks
BenchmarkGPT-5-CodexQwen3.5-9B
SciCode—27.5%
WeirdML54.5%—

Agentic & Tool Use GPT-5-Codex leads

GPT-5-Codex: 30.8 (#66), Qwen3.5-9B: 14.4 (#143)

Agentic & Tool Use benchmarks
BenchmarkGPT-5-CodexQwen3.5-9B
Terminal-Bench44.3%9.2%

Reasoning GPT-5-Codex leads

GPT-5-Codex: 30.0 (#80), Qwen3.5-9B: 22.5 (#178)

Reasoning benchmarks
BenchmarkGPT-5-CodexQwen3.5-9B
Kagi LLM Benchmark70.3%—
CritPt—0.3%
Chess Puzzles—12%
DTBench—71.2%
LMCA—24.5%
Epoch Capabilities Index—139.45

Math Not comparable

GPT-5-Codex: —, Qwen3.5-9B: 33.5 (#174)

Math benchmarks
BenchmarkGPT-5-CodexQwen3.5-9B
MathArena Final-Answer Competitions—48.5%
OTIS Mock AIME 2024-2025—61.7%

Knowledge Not comparable

GPT-5-Codex: —, Qwen3.5-9B: 46.0 (#77)

Knowledge benchmarks
BenchmarkGPT-5-CodexQwen3.5-9B
GPQA Diamond—79%

Frequently asked questions

Is GPT-5-Codex better than Qwen3.5-9B?

GPT-5-Codex is the stronger model overall, scoring 37.3 to 33.3 on the Noometry Index. Qwen3.5-9B costs 31× less per token, which makes it the better buy when GPT-5-Codex's lead doesn't matter for your workload.

Which is cheaper, GPT-5-Codex or Qwen3.5-9B?

Qwen3.5-9B is cheaper. It lists at $0.10 per million input tokens and $0.15 per million output tokens; GPT-5-Codex lists at $1.25 and $10.

Is GPT-5-Codex or Qwen3.5-9B better for coding?

GPT-5-Codex scores higher on coding benchmarks: 41.9 versus 35.3 in the Noometry coding category.

Which has the bigger context window?

GPT-5-Codex does, with 400K tokens against 262K.

How many benchmarks do GPT-5-Codex and Qwen3.5-9B share?

1 benchmark has published results for both models. GPT-5-Codex has 3 scored results on Noometry and Qwen3.5-9B has 10.

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