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Qwen3.5-27B vs Qwen3.5-Flash

Updated October 21, 2026. 34 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.

Qwen3.5-27BQwen
Coding
22.6
Overall
22.9
Output $/M
$2.16
30
Qwen3.5-FlashQwen
Coding
6.2
Overall
No data
Output $/M
$0.26
4
vs boards won of 34 shared

Decision reading

Pick Qwen3.5-27B for coding: it scores 22.6 on the Vibe Coding Index against 6.2 for Qwen3.5-Flash.

Pick Qwen3.5-Flash when output tokens cost 8.3x less, or when the context window is larger, 1M against 262K tokens.

Shared results
34
Qwen3.5-27B only
19
Qwen3.5-Flash only
21
Like-for-like categories
5 of 9

Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.

Which one for your work

Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.

At a glance

Coding index
Qwen3.5-27B 22.6 from 1 benchmark, Qwen3.5-Flash 6.2 from 1 benchmark.
Widest category
Coding, 9.9 points apart on average over 6 shared benchmarks.
Widest single gap
LMArena WebDev: React: Qwen3.5-27B 1346 against Qwen3.5-Flash 1229, 19.5 points apart on a 0 to 100 scale.
Output price
Qwen3.5-27B $2.16 against Qwen3.5-Flash $0.26 per million output tokens, 8.3x apart.
Context window
Qwen3.5-27B takes 262K tokens, Qwen3.5-Flash 1M.

Benchmark by benchmark

First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.

Boards won, where both have a result
CategoryQwen3.5-27BBarsQwen3.5-FlashTies
Coding60
Reasoning30
Math20
Knowledge40
General154
All shared boards304
CodingLike-for-likeFour of these boards feed the Vibe Coding Index60
Coding benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
LMArena WebDev13581244Qwen3.5-27B
LiveCodeBench (Vals AI)Not measured83.3%Only Qwen3.5-Flash measured
SWE-bench Verified (Vals AI)Not measured64.4%Only Qwen3.5-Flash measured
Terminal-Bench Hard (Artificial Analysis run)32.6%Not measuredOnly Qwen3.5-27B measured
WeirdML39.5%Not measuredOnly Qwen3.5-27B measured
ALE-Bench349.4265.9Qwen3.5-27B
LMArena Text: coding14271412Qwen3.5-27B
LMArena Text: software and IT14311416Qwen3.5-27B
LMArena WebDev: React13461229Qwen3.5-27B
LMArena WebDev: HTML13861291Qwen3.5-27B
Neither model has a result on the other 28 boards here
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
Intelligence benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
AA Intelligence Index22.9Not measuredOnly Qwen3.5-27B measured
Epoch Capabilities IndexNot measured143.5Only Qwen3.5-Flash measured
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
Agentic work benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
τ²-Bench Telecom93.9%Not measuredOnly Qwen3.5-27B measured
Vending-Bench 2$202Not measuredOnly Qwen3.5-27B measured
Neither model has a result on the other 37 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index30
Reasoning benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
GPQA DiamondNot measured82.8%Only Qwen3.5-Flash measured
MMMU Pro (Vals AI)Not measured81.9%Only Qwen3.5-Flash measured
GPQA Diamond (Artificial Analysis run)85.8%Not measuredOnly Qwen3.5-27B measured
Humanity's Last Exam (Artificial Analysis run)23.9%Not measuredOnly Qwen3.5-27B measured
GPQA Diamond (Epoch AI run)Not measured82.3%Only Qwen3.5-Flash measured
Chess puzzlesNot measured14.0%Only Qwen3.5-Flash measured
Mystery game puzzlesNot measured20.0%Only Qwen3.5-Flash measured
LMArena Text: hard prompts14151403Qwen3.5-27B
LMArena Text: expert14271407Qwen3.5-27B
LMArena Text: hard prompts in English14291409Qwen3.5-27B
LMArena Vision: diagrams1249Not measuredOnly Qwen3.5-27B measured
LMArena Vision: homework1256Not measuredOnly Qwen3.5-27B measured
Neither model has a result on the other 9 boards here
MathLike-for-likePublic boards, shown as published, kept out of the index20
Math benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
AIMENot measured92.5%Only Qwen3.5-Flash measured
OTIS Mock AIMENot measured84.4%Only Qwen3.5-Flash measured
FrontierMath, tiers 1 to 3Not measured18.2%Only Qwen3.5-Flash measured
LMArena Text: math14291407Qwen3.5-27B
LMArena Text: mathematical work14291413Qwen3.5-27B
Neither model has a result on the other 8 boards here
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index40
Knowledge benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
MMLU ProNot measured84.1%Only Qwen3.5-Flash measured
LegalBench (Vals AI)Not measured84.3%Only Qwen3.5-Flash measured
CaseLaw (Vals AI)Not measured56.0%Only Qwen3.5-Flash measured
CorpFin (Vals AI)Not measured63.6%Only Qwen3.5-Flash measured
TaxEval (Vals AI)Not measured72.2%Only Qwen3.5-Flash measured
MortgageTax (Vals AI)Not measured67.4%Only Qwen3.5-Flash measured
MedCode (Vals AI)Not measured33.0%Only Qwen3.5-Flash measured
SimpleQA VerifiedNot measured20.3%Only Qwen3.5-Flash measured
LMArena Text: science14371415Qwen3.5-27B
LMArena Text: medicine and healthcare14251407Qwen3.5-27B
LMArena Text: legal and government14051398Qwen3.5-27B
LMArena Text: business and finance13991394Qwen3.5-27B
Neither model has a result on the other 5 boards here
Web designNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Web design benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
Neither model has a result on 9 boards here
GeneralLike-for-likePublic boards, shown as published, kept out of the index154
General benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
SAGE (Vals AI)Not measured42.5%Only Qwen3.5-Flash measured
MedScribe (Vals AI)Not measured70.6%Only Qwen3.5-Flash measured
IFBench75.6%Not measuredOnly Qwen3.5-27B measured
Long context reasoning (AA-LCR)77.7%Not measuredOnly Qwen3.5-27B measured
DTBench82.4%82.9%Qwen3.5-Flash
LMCA34.0%29.1%Qwen3.5-27B
LMArena Text14091397Qwen3.5-27B
LMArena Text: instruction following13931374Qwen3.5-27B
LMArena Text: creative writing13621343Qwen3.5-27B
LMArena Vision1241Not measuredOnly Qwen3.5-27B measured
LMArena Text: English14251404Qwen3.5-27B
LMArena Text: non-English13901385Qwen3.5-27B
LMArena Text: Chinese14781445Qwen3.5-27B
LMArena Text: German13921390Qwen3.5-27B
LMArena Text: Japanese13461369Qwen3.5-Flash
LMArena Text: Korean13591344Qwen3.5-27B
LMArena Text: French14101413Qwen3.5-Flash
LMArena Text: Spanish14071400Qwen3.5-27B
LMArena Text: Russian13901380Qwen3.5-27B
LMArena Text: Polish13751376Qwen3.5-Flash
LMArena Text: multi-turn14101393Qwen3.5-27B
LMArena Text: longer queries14131392Qwen3.5-27B
LMArena Text: writing and language13801369Qwen3.5-27B
LMArena Text: entertainment and media13631347Qwen3.5-27B
LMArena Vision: English1246Not measuredOnly Qwen3.5-27B measured
LMArena Vision: Chinese1301Not measuredOnly Qwen3.5-27B measured
LMArena Vision: reading text1246Not measuredOnly Qwen3.5-27B measured
LMArena Vision: humor1227Not measuredOnly Qwen3.5-27B measured
LMArena Vision: captioning1170Not measuredOnly Qwen3.5-27B measured
LMArena Vision: recognizing things1210Not measuredOnly Qwen3.5-27B measured
LMArena Vision: creative writing1224Not measuredOnly Qwen3.5-27B measured
Neither model has a result on the other 15 boards here
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Image generation benchmarks for Qwen3.5-27B and Qwen3.5-Flash
BenchmarkQwen3.5-27BQwen3.5-FlashLeader
Neither model has a result on 5 boards here

What each workload costs

Three fixed token mixes at each model's listed price, so per-token rates become a bill.

Chat turn

1K input + 500 output tokens

Qwen3.5-27B$0.0014Fits in one request
Qwen3.5-Flash$0.0002Fits in one request

Qwen3.5-Flash costs less

Repository review

50K input + 3K output tokens

Qwen3.5-27B$0.020Fits in one request
Qwen3.5-Flash$0.0040Fits in one request

Qwen3.5-Flash costs less

Agent loop

200K input + 10K output tokens

Qwen3.5-27B$0.076Fits in one request
Qwen3.5-Flash$0.016Fits in one request

Qwen3.5-Flash costs less

Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.

Specification differences

The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.

Specifications of Qwen3.5-27B and Qwen3.5-Flash
SpecificationQwen3.5-27BQwen3.5-Flash
MakerQwenQwen
WeightsOpen weightsNo public weights listed
ReleasedFebruary 25, 2026February 25, 2026
Context window262K1M
Input $/Mtok$0.27$0.065
Output $/Mtok$2.16$0.26
Coding index22.66.2
Independent measurements behind it11
Cost per solved taskNot computable$0.40
SourceOpenRouter listingOpenRouter listing

Questions

Is Qwen3.5-27B better than Qwen3.5-Flash for coding?

Pick Qwen3.5-27B for coding: it scores 22.6 on the Vibe Coding Index against 6.2 for Qwen3.5-Flash. Pick Qwen3.5-Flash when output tokens cost 8.3x less, or when the context window is larger, 1M against 262K tokens.

Which is cheaper, Qwen3.5-27B or Qwen3.5-Flash?

Qwen3.5-27B costs $0.27 per million input tokens and $2.16 per million output tokens; Qwen3.5-Flash costs $0.065 and $0.26. Cost per solved task is known for Qwen3.5-Flash only.

Which has the bigger context window, Qwen3.5-27B or Qwen3.5-Flash?

Qwen3.5-Flash, with 1M tokens against 262K.

How many benchmarks is the Qwen3.5-27B vs Qwen3.5-Flash comparison based on?

34 benchmarks have a result for both models as of October 21, 2026. Qwen3.5-27B's coding index rests on 1 independent benchmark and Qwen3.5-Flash's on 1. Where only one model has a result, the page says so instead of naming a winner.

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