Model comparison

GPT-5.1 vs Qwen3.5-Flash

GPT-5.1 is the stronger model overall, scoring 49.0 to 42.5 on the Noometry Index. Qwen3.5-Flash costs 20× less per token, which makes it the better buy when GPT-5.1's lead doesn't matter for your workload.

Last verified . 31 shared benchmarks.

GPT-5.1 OpenAI

49.0

Rank #53 Confirmed

Qwen3.5-Flash Alibaba (Qwen)

42.5

Rank #112 Confirmed

Summary

  • They share 31 benchmarks with published results for both. GPT-5.1 scores higher in 8 categories and Qwen3.5-Flash in 0 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-5.1 leads 52.2 to 37.4.
  • The biggest single-benchmark swing is SimpleQA Verified: 48% for GPT-5.1 and 20.3% for Qwen3.5-Flash.
  • Qwen3.5-Flash is cheaper at $0.10 / $0.40 per million input/output tokens, against $1.25 / $10 for GPT-5.1.
  • Qwen3.5-Flash accepts more context: 1M tokens versus 400K.

Side by side

GPT-5.1 and Qwen3.5-Flash specifications
GPT-5.1Qwen3.5-Flash
ProviderOpenAIAlibaba (Qwen)
Noometry Index49.042.5
Released2025-11-132026-02-23
WeightsProprietaryProprietary
Context window400K1M
Max output128K66K
Input $ / M tokens$1.25$0.10
Output $ / M tokens$10$0.40
Results tracked6332

Sponsored placements are available on pages like this one. Advertise on Noometry

Category by category

Coding GPT-5.1 leads

GPT-5.1: 46.4 (#66), Qwen3.5-Flash: 34.2 (#242)

Coding benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
LMArena WebDev13951244
LMArena Coding14541412
ALE-Bench1,192221.8
SWE-bench Verified68%—
SWE-bench Verified (bash only)66%—
SciCode43.3%—
GSO13.7%—
WeirdML60.8%—
LiveBench Coding72.5%—

Agentic & Tool Use Not comparable

GPT-5.1: 32.7 (#60), Qwen3.5-Flash: —

Agentic & Tool Use benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
Vending-Bench 21,473462.69
Terminal-Bench47.6%—
DeepResearch Bench42.8%—
LMArena Search1199—

Reasoning GPT-5.1 leads

GPT-5.1: 39.8 (#58), Qwen3.5-Flash: 33.7 (#72)

Reasoning benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
Chess Puzzles32%21%
LMArena Hard Prompts14571403
Mystery Game Puzzles19%20%
DTBench90.1%82.9%
LMCA43.9%29.1%
Epoch Capabilities Index149.64143.98
ARC-AGI-217.6%—
SimpleBench53.2%—
ARC-AGI-172.8%—
CritPt4.9%—
EnigmaEval11.2%—
LiveBench Reasoning95.8%—
LiveBench Data Analysis72.1%—
ForecastBench58.1—
LiveBench78.8%—

Math GPT-5.1 leads

GPT-5.1: 52.2 (#51), Qwen3.5-Flash: 37.4 (#158)

Math benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
OTIS Mock AIME 2024-202588.6%84.4%
LMArena Math14471407
FrontierMath (Feb 2025 set)31%6.2%
FrontierMath Tier 4 (v1)12.5%0%
FrontierMath (Tiers 1-3)—18.2%
Omni-MATH46.4%—
LiveBench Math94.5%—

Knowledge GPT-5.1 leads

GPT-5.1: 50.6 (#71), Qwen3.5-Flash: 43.2 (#93)

Knowledge benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
GPQA Diamond87.6%82.3%
SimpleQA Verified48%20.3%
Vectara Hallucination Rate10.9%10.5%
LMArena Expert14701407
Humanity's Last Exam23.7%—
MMLU-Pro57.9%—
GPQA (HELM)44.2%—

Multimodal Not comparable

GPT-5.1: 44.8 (#19), Qwen3.5-Flash: —

Multimodal benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
LMArena Vision1250—
VPCT58.7%—
LMArena Document1403—

Multilingual GPT-5.1 leads

GPT-5.1: 53.8 (#56), Qwen3.5-Flash: 50.5 (#121)

Multilingual benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
LMArena Non-English14311385
LMArena Chinese14951446
LMArena French14501412
LMArena German14381390
LMArena Japanese14531368
LMArena Korean14011344
LMArena Russian14351379
LMArena Spanish14331400

Instruction Following GPT-5.1 leads

GPT-5.1: 83.9 (#1), Qwen3.5-Flash: 72.6 (#139)

Instruction Following benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
LMArena Instruction Following14431374
LiveBench Instruction Following93.3%—
IFEval93.5%—

Long Context GPT-5.1 leads

GPT-5.1: 47.6 (#14), Qwen3.5-Flash: 42.4 (#124)

Long Context benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
LMArena Longer Query14471392
CL-bench23.7%—
CL-bench Life17.3%—

Writing & Preference GPT-5.1 leads

GPT-5.1: 64.5 (#55), Qwen3.5-Flash: 57.9 (#122)

Writing & Preference benchmarks
BenchmarkGPT-5.1Qwen3.5-Flash
LMArena Text14431397
LMArena Creative Writing14271343
LMArena Multi-Turn14501393
WildBench86.3%—
LiveBench Language80.2%—

Frequently asked questions

Is GPT-5.1 better than Qwen3.5-Flash?

GPT-5.1 is the stronger model overall, scoring 49.0 to 42.5 on the Noometry Index. Qwen3.5-Flash costs 20× less per token, which makes it the better buy when GPT-5.1's lead doesn't matter for your workload.

Which is cheaper, GPT-5.1 or Qwen3.5-Flash?

Qwen3.5-Flash is cheaper. It lists at $0.10 per million input tokens and $0.40 per million output tokens; GPT-5.1 lists at $1.25 and $10.

Is GPT-5.1 or Qwen3.5-Flash better for coding?

GPT-5.1 scores higher on coding benchmarks: 46.4 versus 34.2 in the Noometry coding category.

Which has the bigger context window?

Qwen3.5-Flash does, with 1M tokens against 400K.

How many benchmarks do GPT-5.1 and Qwen3.5-Flash share?

31 benchmarks have published results for both models. GPT-5.1 has 63 scored results on Noometry and Qwen3.5-Flash has 32.

Related comparisons

Go deeper