Gemini 3.1 Pro Preview vs Qwen3.5-Flash

Qwen3.5-Flash leads Gemini 3.1 Pro Preview on coding, 41.1 to 32.3 on the Vibe Coding Index, and Qwen3.5-Flash costs 46.2x less per output token ($0.26 vs $12.00 per million). Updated October 22, 2026; 54 benchmarks have a result for both.

Replace Gemini 3.1 Pro Preview Replace Qwen3.5-Flash

Gemini 3.1 Pro PreviewGoogle

Coding: 32.3
Overall: 54.0
Output $/M: $12.00

Qwen3.5-FlashQwen

Coding: 41.1
Overall: 50.1
Output $/M: $0.26

vs boards won of 54 shared

Gemini 3.1 Pro Preview or Qwen3.5-Flash: which to pick

Pick Qwen3.5-Flash for coding: it scores 41.1 on the Vibe Coding Index against 32.3 for Gemini 3.1 Pro Preview, though on 2 benchmarks against 4.

Pick Gemini 3.1 Pro Preview for a larger context window (1.05M against 1M tokens) and work measured by LMArena WebDev or LiveCodeBench (Vals AI), where it leads.

Model AGemini 3.1 Pro PreviewGoogle32.3/1004 independent benchmarks$0.99 per solved task Model BQwen3.5-FlashQwen41.1/1002 independent benchmarks$0.40 per solved task

54791

Shared results: 54
Gemini 3.1 Pro Preview only: 79
Qwen3.5-Flash only: 1
Like-for-like categories: 5 of 9

Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.

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.

Coding
Vibe Coding Index, six public coding benchmarks
Qwen3.5-Flash
Qwen3.5-Flash scores 41.1 against 32.3.
4 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
No call
Only Gemini 3.1 Pro Preview has a AA Intelligence Index result, 29.7.
Directional only
Agentic work
AA Agentic Index
No call
Only Gemini 3.1 Pro Preview has a AA Agentic Index result, 8.2.
Directional only
Reasoning
GPQA Diamond
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview leads, 95.5% against 82.8%.
Same board, both measured
Math
AIME
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview leads, 98.1% against 92.5%.
Same board, both measured
Knowledge
MMLU Pro
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview leads, 91.0% against 84.1%.
Same board, both measured
Web design
Design Arena: websites
No call
Only Gemini 3.1 Pro Preview has a Design Arena: websites result, 1233.
Directional only
Long documents
Listed context window
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Qwen3.5-Flash
Gemini 3.1 Pro Preview $0.0080, Qwen3.5-Flash $0.0002 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Qwen3.5-Flash
Gemini 3.1 Pro Preview $0.99, Qwen3.5-Flash $0.40.
Published attempt cost and pass rate

At a glance

Coding index: Gemini 3.1 Pro Preview 32.3 from 4 benchmarks, Qwen3.5-Flash 41.1 from 2 benchmarks.
Widest category: Coding, 21.3 points apart on average over 8 shared benchmarks.
Widest single gap: SimpleQA Verified: Gemini 3.1 Pro Preview 73.5% against Qwen3.5-Flash 20.3%, 53.2 points apart on a 0 to 100 scale.
Output price: Gemini 3.1 Pro Preview $12.00 against Qwen3.5-Flash $0.26 per million output tokens, 46.2x apart.
Context window: Gemini 3.1 Pro Preview takes 1.05M 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
Category	Gemini 3.1 Pro Preview	Bars	Qwen3.5-Flash	Ties
Coding	8		0
Reasoning	8		0
Math	5		0
Knowledge	12		0
General	21		0
All shared boards	54		0

CodingLike-for-likeSix of these boards feed the Vibe Coding Index80

Coding benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
LMArena WebDev	1447	1244	Gemini 3.1 Pro Preview
AA Coding Index	68.8	Not measured	Only Gemini 3.1 Pro Preview measured
LiveCodeBench (Vals AI)	88.5%	83.3%	Gemini 3.1 Pro Preview
SWE-bench Verified (Vals AI)	78.8%	64.4%	Gemini 3.1 Pro Preview
Terminal-Bench 4 (Vals AI)	2.5%	Not measured	Only Gemini 3.1 Pro Preview measured
Vibe Code Bench (Vals AI)	32.0%	Not measured	Only Gemini 3.1 Pro Preview measured
Code migration (Vals AI)	17.3%	Not measured	Only Gemini 3.1 Pro Preview measured
ProgramBench (Vals AI)	0.0%	Not measured	Only Gemini 3.1 Pro Preview measured
IOI (Vals AI)	51.8%	Not measured	Only Gemini 3.1 Pro Preview measured
Terminal-Bench 2.1 (Vals AI)	70.8%	Not measured	Only Gemini 3.1 Pro Preview measured
Vibe Code Bench 1-100 (Vals AI)	6.7%	Not measured	Only Gemini 3.1 Pro Preview measured
SciCode	58.7%	Not measured	Only Gemini 3.1 Pro Preview measured
Terminal-Bench Hard (Artificial Analysis run)	53.8%	Not measured	Only Gemini 3.1 Pro Preview measured
Terminal-Bench	80.2%	Not measured	Only Gemini 3.1 Pro Preview measured
GSO-Bench	22.6%	Not measured	Only Gemini 3.1 Pro Preview measured
WeirdML	72.1%	Not measured	Only Gemini 3.1 Pro Preview measured
MirrorCode	8.9%	Not measured	Only Gemini 3.1 Pro Preview measured
ALE-Bench	1160.6	265.9	Gemini 3.1 Pro Preview
LMArena Text: coding	1484	1412	Gemini 3.1 Pro Preview
LMArena Text: software and IT	1487	1416	Gemini 3.1 Pro Preview
LMArena WebDev: React	1438	1229	Gemini 3.1 Pro Preview
LMArena WebDev: HTML	1490	1291	Gemini 3.1 Pro Preview
LMArena WebDev: from an image	1481	Not measured	Only Gemini 3.1 Pro Preview measured
SciCode	14.3%	Not measured	Only Gemini 3.1 Pro Preview measured
Neither model has a result on the other 15 boards here

IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared

Intelligence benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
AA Intelligence Index	29.7	Not measured	Only Gemini 3.1 Pro Preview measured
Epoch Capabilities Index	Not measured	143.5	Only Qwen3.5-Flash measured

Agentic workDirectional onlyPublic boards, shown as published, kept out of the index24 boards, none shared

Agentic work benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
AA Agentic Index	8.2	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: agents building web apps	1125	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: agents building full-stack apps	1068	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: agents building mobile apps	1094	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: agents building Android apps	1049	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: agents building Godot games	1236	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: agents building games	1113	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: HTML slides	1103	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: PowerPoint slides	1041	Not measured	Only Gemini 3.1 Pro Preview measured
SREBench (Vals AI)	0.0%	Not measured	Only Gemini 3.1 Pro Preview measured
Finance Agent (Vals AI)	43.0%	Not measured	Only Gemini 3.1 Pro Preview measured
Tax Agent Bench (Vals AI)	9.3%	Not measured	Only Gemini 3.1 Pro Preview measured
Legal Research Bench (Vals AI)	20.7%	Not measured	Only Gemini 3.1 Pro Preview measured
Excel Modeling Benchmark (Vals AI)	52.6%	Not measured	Only Gemini 3.1 Pro Preview measured
BioMysteryBench (Vals AI)	60.0%	Not measured	Only Gemini 3.1 Pro Preview measured
Terminal-Bench-Science (Vals AI)	1.4%	Not measured	Only Gemini 3.1 Pro Preview measured
Vals Science Index	27.4%	Not measured	Only Gemini 3.1 Pro Preview measured
τ²-Bench Telecom	95.6%	Not measured	Only Gemini 3.1 Pro Preview measured
APEX-Agents	35.1%	Not measured	Only Gemini 3.1 Pro Preview measured
METR time horizons	77.0%	Not measured	Only Gemini 3.1 Pro Preview measured
BALROG	57.0%	Not measured	Only Gemini 3.1 Pro Preview measured
DeepResearch Bench	47.8%	Not measured	Only Gemini 3.1 Pro Preview measured
PostTrainBench	22.0%	Not measured	Only Gemini 3.1 Pro Preview measured
Vending-Bench 2	$911	Not measured	Only Gemini 3.1 Pro Preview measured
Neither model has a result on the other 17 boards here

ReasoningLike-for-likePublic boards, shown as published, kept out of the index80

Reasoning benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
GPQA Diamond	95.5%	82.8%	Gemini 3.1 Pro Preview
MysteryMechanism (Vals AI)	20.7%	Not measured	Only Gemini 3.1 Pro Preview measured
MMMU Pro (Vals AI)	88.2%	81.9%	Gemini 3.1 Pro Preview
GPQA Diamond (Artificial Analysis run)	94.1%	Not measured	Only Gemini 3.1 Pro Preview measured
Humanity's Last Exam (Artificial Analysis run)	47.0%	Not measured	Only Gemini 3.1 Pro Preview measured
GPQA Diamond (Epoch AI run)	94.4%	82.3%	Gemini 3.1 Pro Preview
ARC-AGI	98.0%	Not measured	Only Gemini 3.1 Pro Preview measured
ARC-AGI-2	77.1%	Not measured	Only Gemini 3.1 Pro Preview measured
SimpleBench	79.6%	Not measured	Only Gemini 3.1 Pro Preview measured
Chess puzzles	51.0%	14.0%	Gemini 3.1 Pro Preview
Mystery game puzzles	34.0%	20.0%	Gemini 3.1 Pro Preview
EBR-bench	14.3%	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Text: hard prompts	1485	1403	Gemini 3.1 Pro Preview
LMArena Text: expert	1483	1407	Gemini 3.1 Pro Preview
LMArena Text: hard prompts in English	1480	1409	Gemini 3.1 Pro Preview
LMArena Vision: diagrams	1311	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Vision: homework	1316	Not measured	Only Gemini 3.1 Pro Preview measured
Neither model has a result on the other 5 boards here

MathLike-for-likePublic boards, shown as published, kept out of the index50

Math benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
AIME	98.1%	92.5%	Gemini 3.1 Pro Preview
OTIS Mock AIME	95.6%	84.4%	Gemini 3.1 Pro Preview
FrontierMath, tiers 1 to 3	59.6%	18.2%	Gemini 3.1 Pro Preview
FrontierMath, tier 4	26.8%	Not measured	Only Gemini 3.1 Pro Preview measured
ProofBench	26.0%	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Text: math	1486	1407	Gemini 3.1 Pro Preview
LMArena Text: mathematical work	1478	1413	Gemini 3.1 Pro Preview
Neither model has a result on the other 6 boards here

KnowledgeLike-for-likePublic boards, shown as published, kept out of the index120

Knowledge benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
MMLU Pro	91.0%	84.1%	Gemini 3.1 Pro Preview
LegalBench (Vals AI)	87.4%	84.3%	Gemini 3.1 Pro Preview
CaseLaw (Vals AI)	64.8%	56.0%	Gemini 3.1 Pro Preview
CorpFin (Vals AI)	64.5%	63.6%	Gemini 3.1 Pro Preview
TaxEval (Vals AI)	72.9%	72.2%	Gemini 3.1 Pro Preview
MortgageTax (Vals AI)	69.4%	67.4%	Gemini 3.1 Pro Preview
MedQA (Vals AI)	96.4%	Not measured	Only Gemini 3.1 Pro Preview measured
MedCode (Vals AI)	59.1%	33.0%	Gemini 3.1 Pro Preview
SimpleQA Verified	73.5%	20.3%	Gemini 3.1 Pro Preview
LMArena Text: science	1497	1415	Gemini 3.1 Pro Preview
LMArena Text: medicine and healthcare	1486	1407	Gemini 3.1 Pro Preview
LMArena Text: legal and government	1487	1398	Gemini 3.1 Pro Preview
LMArena Text: business and finance	1459	1394	Gemini 3.1 Pro Preview
FACTS Benchmark Suite	67.4%	Not measured	Only Gemini 3.1 Pro Preview measured
Neither model has a result on the other 4 boards here

Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared

Web design benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
Design Arena: websites	1233	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: UI components	1224	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: game dev	1202	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: data viz	1209	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: 3D	1234	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: all code categories	1231	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: SVG	1285	Not measured	Only Gemini 3.1 Pro Preview measured
Design Arena: ASCII art	1270	Not measured	Only Gemini 3.1 Pro Preview measured
Neither model has a result on the other 1 board here

GeneralLike-for-likePublic boards, shown as published, kept out of the index210

General benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
Public Benefits Bench (Vals AI)	53.8%	Not measured	Only Gemini 3.1 Pro Preview measured
SAGE (Vals AI)	48.7%	42.5%	Gemini 3.1 Pro Preview
MedScribe (Vals AI)	76.1%	70.6%	Gemini 3.1 Pro Preview
Vals Multimodal Index	56.1%	Not measured	Only Gemini 3.1 Pro Preview measured
IFBench	77.1%	Not measured	Only Gemini 3.1 Pro Preview measured
Long context reasoning (AA-LCR)	82.0%	Not measured	Only Gemini 3.1 Pro Preview measured
DTBench	97.1%	82.9%	Gemini 3.1 Pro Preview
LMCA	53.8%	29.1%	Gemini 3.1 Pro Preview
CL-bench	20.8%	Not measured	Only Gemini 3.1 Pro Preview measured
Furniture assembly	26.7%	Not measured	Only Gemini 3.1 Pro Preview measured
ExploitBench	26.1%	Not measured	Only Gemini 3.1 Pro Preview measured
CL-bench Life	16.9%	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Text	1480	1397	Gemini 3.1 Pro Preview
LMArena Text: instruction following	1466	1374	Gemini 3.1 Pro Preview
LMArena Text: creative writing	1482	1343	Gemini 3.1 Pro Preview
LMArena Vision	1296	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Text: English	1478	1404	Gemini 3.1 Pro Preview
LMArena Text: non-English	1476	1385	Gemini 3.1 Pro Preview
LMArena Text: Chinese	1527	1445	Gemini 3.1 Pro Preview
LMArena Text: German	1490	1390	Gemini 3.1 Pro Preview
LMArena Text: Japanese	1491	1369	Gemini 3.1 Pro Preview
LMArena Text: Korean	1455	1344	Gemini 3.1 Pro Preview
LMArena Text: French	1487	1413	Gemini 3.1 Pro Preview
LMArena Text: Spanish	1481	1400	Gemini 3.1 Pro Preview
LMArena Text: Russian	1497	1380	Gemini 3.1 Pro Preview
LMArena Text: Polish	1498	1376	Gemini 3.1 Pro Preview
LMArena Text: multi-turn	1487	1393	Gemini 3.1 Pro Preview
LMArena Text: longer queries	1482	1392	Gemini 3.1 Pro Preview
LMArena Text: writing and language	1481	1369	Gemini 3.1 Pro Preview
LMArena Text: entertainment and media	1465	1347	Gemini 3.1 Pro Preview
LMArena Vision: English	1287	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Vision: Chinese	1364	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Vision: reading text	1304	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Vision: humor	1322	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Vision: captioning	1345	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Vision: recognizing things	1330	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Vision: creative writing	1324	Not measured	Only Gemini 3.1 Pro Preview measured
LMArena Document	1444	Not measured	Only Gemini 3.1 Pro Preview measured
Neither model has a result on the other 8 boards here

Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared

Image generation benchmarks for Gemini 3.1 Pro Preview and Qwen3.5-Flash
Benchmark	Gemini 3.1 Pro Preview	Qwen3.5-Flash	Leader
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

Gemini 3.1 Pro Preview$0.0080Fits in one request

Qwen3.5-Flash$0.0002Fits in one request

Qwen3.5-Flash costs less

Repository review

50K input + 3K output tokens

Gemini 3.1 Pro Preview$0.136Fits in one request

Qwen3.5-Flash$0.0040Fits in one request

Qwen3.5-Flash costs less

Agent loop

200K input + 10K output tokens

Gemini 3.1 Pro Preview$0.520Fits 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 Gemini 3.1 Pro Preview and Qwen3.5-Flash
Specification	Google Gemini 3.1 Pro Preview	Qwen3.5-Flash
Maker	Google	Qwen
Weights	No public weights listed	No public weights listed
Released	February 19, 2026	February 25, 2026
Context window	1.05M	1M
Input $/Mtok	$2.00	$0.065
Output $/Mtok	$12.00	$0.26
Coding index	32.3	41.1
Independent measurements behind it	4	2
Cost per solved task	$0.99	$0.40
Source	OpenRouter listing	OpenRouter listing

Questions

Is Gemini 3.1 Pro Preview better than Qwen3.5-Flash for coding?

Pick Qwen3.5-Flash for coding: it scores 41.1 on the Vibe Coding Index against 32.3 for Gemini 3.1 Pro Preview, though on 2 benchmarks against 4. Pick Gemini 3.1 Pro Preview for a larger context window (1.05M against 1M tokens) and work measured by LMArena WebDev or LiveCodeBench (Vals AI), where it leads.

Which is cheaper, Gemini 3.1 Pro Preview or Qwen3.5-Flash?

Gemini 3.1 Pro Preview costs $2.00 per million input tokens and $12.00 per million output tokens; Qwen3.5-Flash costs $0.065 and $0.26. Per solved SWE-bench Verified task, Gemini 3.1 Pro Preview costs $0.99 and Qwen3.5-Flash $0.40.

Which has the bigger context window, Gemini 3.1 Pro Preview or Qwen3.5-Flash?

Gemini 3.1 Pro Preview, with 1.05M tokens against 1M.

How many benchmarks is the Gemini 3.1 Pro Preview vs Qwen3.5-Flash comparison based on?

54 benchmarks have a result for both models as of October 22, 2026. Gemini 3.1 Pro Preview's coding index rests on 4 independent benchmarks and Qwen3.5-Flash's on 2. Where only one model has a result, the page says so instead of naming a winner.

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Gemini 3.1 Pro Preview or Qwen3.5-Flash: which to pick

Which one for your work

Coding

Intelligence

Agentic work

Reasoning

Math

Knowledge

Web design

Long documents

Everyday cost

Cost per solved task

At a glance

Benchmark by benchmark

What each workload costs

Chat turn

Repository review

Agent loop

Specification differences

Questions

Compare next