GPT-5.3 Codex vs Qwen3.6 Plus

Side-by-side benchmark comparison across agentic, coding, multimodal, knowledge, reasoning, and math workflows.

Agentic
Coding
Multimodal & Grounded
Reasoning
Knowledge
Instruction Following
Multilingual
Mathematics

GPT-5.3 Codex· Qwen3.6 Plus

Quick Verdict

Pick GPT-5.3 Codex if you want the stronger benchmark profile. Qwen3.6 Plus only becomes the better choice if instruction following is the priority or you want the cheaper token bill.

GPT-5.3 Codex is clearly ahead on the aggregate, 85 to 69. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.3 Codex's sharpest advantage is in reasoning, where it averages 92.5 against 62. The single biggest benchmark swing on the page is LongBench v2, 92% to 62%. Qwen3.6 Plus does hit back in instruction following, so the answer changes if that is the part of the workload you care about most.

GPT-5.3 Codex is also the more expensive model on tokens at $2.50 input / $10.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Qwen3.6 Plus. That is roughly Infinityx on output cost alone. Qwen3.6 Plus gives you the larger context window at 1M, compared with 400K for GPT-5.3 Codex.

Operational tradeoffs

Price$2.50 / $10.00Free*
Speed79 t/sN/A
TTFT88.26sN/A
Context400K1M

Decision framing

BenchLM keeps the benchmark table and the operator tradeoffs on the same page so a better score does not hide a materially slower, pricier, or smaller-context model.

Runtime metrics show N/A when BenchLM does not have a sourced snapshot for that exact model. The scoring rules and freshness policy are documented on the methodology page.

BenchmarkGPT-5.3 CodexQwen3.6 Plus
AgenticGPT-5.3 Codex wins
Terminal-Bench 2.077.3%61.6%
BrowseComp88%
OSWorld-Verified64.7%62.5%
Claw-Eval58.7%
QwenClawBench57.2%
QwenWebBench1502
TAU3-Bench70.7%
VITA-Bench44.3%
DeepPlanning41.5%
Toolathlon39.8%
MCP Atlas48.2%
MCP-Tasks74.1%
WideResearch74.3%
CodingGPT-5.3 Codex wins
SWE-bench Verified85%78.8%
LiveCodeBench85%
SWE-bench Pro56.8%56.6%
SWE-Rebench58.2%
React Native Evals80.9%
SWE Multilingual73.8%
LiveCodeBench v687.1%
NL2Repo37.9%
Multimodal & GroundedGPT-5.3 Codex wins
MMMU-Pro89%78.8%
OfficeQA Pro94%
MMMU86.0%
RealWorldQA85.4%
OmniDocBench 1.591.2%
Video-MME (with subtitle)87.8%
Video-MME (w/o subtitle)84.2%
MathVision88.0%
We-Math89.0%
DynaMath88.0%
MStar83.3%
SimpleVQA67.3%
ChatCVQA81.5%
MMLongBench-Doc62.0%
CC-OCR83.4%
AI2D_TEST94.4%
CountBench97.6%
RefCOCO (avg)93.5%
ODINW1351.8%
ERQA65.7%
VideoMMMU84.0%
MLVU (M-Avg)86.7%
ScreenSpot Pro68.2%
ReasoningGPT-5.3 Codex wins
BBH98%
LongBench v292%62%
MRCRv293%
AI-Needle68.3%
KnowledgeGPT-5.3 Codex wins
MMLU-Pro90%88.5%
HLE44%28.8%
FrontierScience90%
SimpleQA95%
GPQA90.4%
SuperGPQA71.6%
MMLU-Redux94.5%
C-Eval93.3%
Instruction FollowingQwen3.6 Plus wins
IFEval93%94.3%
IFBench74.2%
MultilingualGPT-5.3 Codex wins
MGSM96%
MMLU-ProX91%84.7%
NOVA-6357.9%
INCLUDE85.1%
PolyMath77.4%
VWT2k-lite84.3%
MAXIFE88.2%
Mathematics
AIME 202399%
AIME 202499%
AIME 202598%
HMMT Feb 202395%
HMMT Feb 202497%
HMMT Feb 202596%
BRUMO 202596%
MATH-50099%
AIME2695.3%
HMMT Feb 202596.7%
HMMT Nov 202594.6%
HMMT Feb 202687.8%
MMAnswerBench83.8%
Frequently Asked Questions (8)

Which is better, GPT-5.3 Codex or Qwen3.6 Plus?

GPT-5.3 Codex is ahead overall, 85 to 69. The biggest single separator in this matchup is LongBench v2, where the scores are 92% and 62%.

Which is better for knowledge tasks, GPT-5.3 Codex or Qwen3.6 Plus?

GPT-5.3 Codex has the edge for knowledge tasks in this comparison, averaging 76.9 versus 66. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for coding, GPT-5.3 Codex or Qwen3.6 Plus?

GPT-5.3 Codex has the edge for coding in this comparison, averaging 68.6 versus 64.9. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.

Which is better for reasoning, GPT-5.3 Codex or Qwen3.6 Plus?

GPT-5.3 Codex has the edge for reasoning in this comparison, averaging 92.5 versus 62. Inside this category, LongBench v2 is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.3 Codex or Qwen3.6 Plus?

GPT-5.3 Codex has the edge for agentic tasks in this comparison, averaging 75.6 versus 62. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, GPT-5.3 Codex or Qwen3.6 Plus?

GPT-5.3 Codex has the edge for multimodal and grounded tasks in this comparison, averaging 91.3 versus 78.8. Inside this category, MMMU-Pro is the benchmark that creates the most daylight between them.

Which is better for instruction following, GPT-5.3 Codex or Qwen3.6 Plus?

Qwen3.6 Plus has the edge for instruction following in this comparison, averaging 94.3 versus 93. Inside this category, IFEval is the benchmark that creates the most daylight between them.

Which is better for multilingual tasks, GPT-5.3 Codex or Qwen3.6 Plus?

GPT-5.3 Codex has the edge for multilingual tasks in this comparison, averaging 92.8 versus 84.7. Inside this category, MMLU-ProX is the benchmark that creates the most daylight between them.

Last updated: April 2, 2026

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