Gemini 3 Flash Preview vs Qwen3.5 Plus 2026-04-20
Gemini 3 Flash Preview leads Qwen3.5 Plus 2026-04-20 on coding, 43.7 to 39.5 on the Vibe Coding Index, and Qwen3.5 Plus 2026-04-20 costs 1.7x less per output token ($1.80 vs $3.00 per million). Updated October 22, 2026; 22 benchmarks have a result for both.
Gemini 3 Flash Preview or Qwen3.5 Plus 2026-04-20: which to pick
Pick Gemini 3 Flash Preview for coding: it scores 43.7 on the Vibe Coding Index against 39.5 for Qwen3.5 Plus 2026-04-20.
Pick Qwen3.5 Plus 2026-04-20 for output tokens 1.7x cheaper ($1.80 vs $3.00 per million) and work measured by CaseLaw (Vals AI), where it leads.
- Shared results
- 22
- Gemini 3 Flash Preview only
- 49
- Qwen3.5 Plus 2026-04-20 only
- 3
- Like-for-like categories
- 6 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
Gemini 3 Flash Preview
Gemini 3 Flash Preview scores 43.7 against 39.5.
2 benchmarks behind each score
Intelligence
AA Intelligence Index
No call
Only Gemini 3 Flash Preview has a AA Intelligence Index result, 26.3.
Directional only
Reasoning
GPQA Diamond
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 87.9% against 87.4%.
Same board, both measured
Math
AIME
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 95.6% against 86.0%.
Same board, both measured
Knowledge
MMLU Pro
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 88.6% against 87.2%.
Same board, both measured
Web design
Design Arena: websites
No call
Only Gemini 3 Flash Preview has a Design Arena: websites result, 1196.
Directional only
Long documents
Listed context window
Gemini 3 Flash Preview
Gemini 3 Flash Preview takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Qwen3.5 Plus 2026-04-20
Gemini 3 Flash Preview $0.0020, Qwen3.5 Plus 2026-04-20 $0.0012 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Gemini 3 Flash Preview
Gemini 3 Flash Preview $0.37, Qwen3.5 Plus 2026-04-20 $1.35.
Published attempt cost and pass rate
At a glance
- Coding index
- Gemini 3 Flash Preview 43.7 from 2 benchmarks, Qwen3.5 Plus 2026-04-20 39.5 from 2 benchmarks.
- Widest category
- Agentic work, 22.7 points apart on average over 1 shared benchmark.
- Widest single gap
- MMMU Pro (Vals AI): Gemini 3 Flash Preview 87.6% against Qwen3.5 Plus 2026-04-20 22.8%, 64.9 points apart on a 0 to 100 scale.
- Output price
- Gemini 3 Flash Preview $3.00 against Qwen3.5 Plus 2026-04-20 $1.80 per million output tokens, 1.7x apart.
- Context window
- Gemini 3 Flash Preview takes 1.05M tokens, Qwen3.5 Plus 2026-04-20 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.
| Category | Gemini 3 Flash Preview | Bars | Qwen3.5 Plus 2026-04-20 | Ties |
|---|---|---|---|---|
| Coding | 4 | 0 | ||
| Agentic work | 1 | 0 | ||
| Reasoning | 5 | 0 | ||
| Math | 2 | 0 | ||
| Knowledge | 6 | 1 | ||
| General | 3 | 0 | ||
| All shared boards | 21 | 1 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index40
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| SWE-bench Verified | 75.8% | Not measured | Only Gemini 3 Flash Preview measured |
| LiveCodeBench (Vals AI) | 85.6% | 85.3% | Gemini 3 Flash Preview |
| SWE-bench Verified (Vals AI) | 75.0% | 71.2% | Gemini 3 Flash Preview |
| Vibe Code Bench (Vals AI) | 20.2% | 15.7% | Gemini 3 Flash Preview |
| Code migration (Vals AI) | 6.4% | Not measured | Only Gemini 3 Flash Preview measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Terminal-Bench 2.1 (Vals AI) | 53.9% | Not measured | Only Gemini 3 Flash Preview measured |
| LiveCodeBench (Artificial Analysis run) | 90.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Terminal-Bench Hard (Artificial Analysis run) | 38.6% | Not measured | Only Gemini 3 Flash Preview measured |
| Terminal-Bench | 64.3% | Not measured | Only Gemini 3 Flash Preview measured |
| GSO-Bench | 9.8% | Not measured | Only Gemini 3 Flash Preview measured |
| WeirdML | 61.6% | Not measured | Only Gemini 3 Flash Preview measured |
| ALE-Bench | 1367.2 | 608.9 | Gemini 3 Flash Preview |
| SciCode | 12.7% | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 25 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| AA Intelligence Index | 26.3 | Not measured | Only Gemini 3 Flash Preview measured |
| Epoch Capabilities Index | Not measured | 146.2 | Only Qwen3.5 Plus 2026-04-20 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1111 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building full-stack apps | 1063 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building mobile apps | 1090 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building Android apps | 1051 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building Godot games | 1161 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: PowerPoint slides | 1036 | Not measured | Only Gemini 3 Flash Preview measured |
| Finance Agent (Vals AI) | 42.5% | Not measured | Only Gemini 3 Flash Preview measured |
| Tax Agent Bench (Vals AI) | 11.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Legal Research Bench (Vals AI) | 18.3% | Not measured | Only Gemini 3 Flash Preview measured |
| Excel Modeling Benchmark (Vals AI) | 26.0% | Not measured | Only Gemini 3 Flash Preview measured |
| τ²-Bench Telecom | 80.4% | Not measured | Only Gemini 3 Flash Preview measured |
| BALROG | 48.1% | Not measured | Only Gemini 3 Flash Preview measured |
| DeepResearch Bench | 49.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Vending-Bench 2 | $3,635 | $1 | Gemini 3 Flash Preview |
| Neither model has a result on the other 27 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| GPQA Diamond | 87.9% | 87.4% | Gemini 3 Flash Preview |
| MMMU Pro (Vals AI) | 87.6% | 22.8% | Gemini 3 Flash Preview |
| GPQA Diamond (Artificial Analysis run) | 89.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Humanity's Last Exam (Artificial Analysis run) | 36.6% | Not measured | Only Gemini 3 Flash Preview measured |
| GPQA Diamond (Epoch AI run) | 89.4% | 84.8% | Gemini 3 Flash Preview |
| ARC-AGI | 84.7% | Not measured | Only Gemini 3 Flash Preview measured |
| ARC-AGI-2 | 33.6% | Not measured | Only Gemini 3 Flash Preview measured |
| SimpleBench | 61.1% | Not measured | Only Gemini 3 Flash Preview measured |
| Chess puzzles | 39.0% | 8.0% | Gemini 3 Flash Preview |
| Mystery game puzzles | 26.0% | 17.0% | Gemini 3 Flash Preview |
| VPCT | 72.6% | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 11 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| AIME | 95.6% | 86.0% | Gemini 3 Flash Preview |
| MGSM (Vals AI) | 93.3% | Not measured | Only Gemini 3 Flash Preview measured |
| AA Math Index | 97.0 | Not measured | Only Gemini 3 Flash Preview measured |
| AIME 2025 (Artificial Analysis run) | 97.0% | Not measured | Only Gemini 3 Flash Preview measured |
| OTIS Mock AIME | 95.6% | 86.7% | Gemini 3 Flash Preview |
| FrontierMath, tiers 1 to 3 | 51.2% | Not measured | Only Gemini 3 Flash Preview measured |
| FrontierMath, tier 4 | 17.1% | Not measured | Only Gemini 3 Flash Preview measured |
| ProofBench | 15.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 5 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index61
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| MMLU Pro | 88.6% | 87.2% | Gemini 3 Flash Preview |
| LegalBench (Vals AI) | 86.9% | 85.1% | Gemini 3 Flash Preview |
| CaseLaw (Vals AI) | 55.8% | 59.7% | Qwen3.5 Plus 2026-04-20 |
| CorpFin (Vals AI) | 66.4% | 65.3% | Gemini 3 Flash Preview |
| TaxEval (Vals AI) | 73.9% | Not measured | Only Gemini 3 Flash Preview measured |
| MortgageTax (Vals AI) | 68.7% | 60.8% | Gemini 3 Flash Preview |
| MedQA (Vals AI) | 95.8% | 95.2% | Gemini 3 Flash Preview |
| MedCode (Vals AI) | 55.9% | Not measured | Only Gemini 3 Flash Preview measured |
| MMLU Pro (Artificial Analysis run) | 89.0% | Not measured | Only Gemini 3 Flash Preview measured |
| SimpleQA Verified | 66.8% | 25.4% | Gemini 3 Flash Preview |
| GeoBench | 88.0% | Not measured | Only Gemini 3 Flash Preview measured |
| FACTS Benchmark Suite | 63.4% | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index4 boards, none shared
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| Design Arena: websites | 1196 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: game dev | 1166 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: 3D | 1183 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: all code categories | 1189 | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 5 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index30
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 51.8% | 30.4% | Gemini 3 Flash Preview |
| MedScribe (Vals AI) | 69.9% | Not measured | Only Gemini 3 Flash Preview measured |
| Vals Multimodal Index | 52.2% | Not measured | Only Gemini 3 Flash Preview measured |
| IFBench | 78.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Long context reasoning (AA-LCR) | 78.0% | Not measured | Only Gemini 3 Flash Preview measured |
| DTBench | 89.1% | 80.5% | Gemini 3 Flash Preview |
| LMCA | 43.1% | 36.4% | Gemini 3 Flash Preview |
| CL-bench | Not measured | 19.8% | Only Qwen3.5 Plus 2026-04-20 measured |
| CL-bench Life | Not measured | 12.4% | Only Qwen3.5 Plus 2026-04-20 measured |
| Neither model has a result on the other 37 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 | 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
Qwen3.5 Plus 2026-04-20 costs less
Repository review
50K input + 3K output tokens
Qwen3.5 Plus 2026-04-20 costs less
Agent loop
200K input + 10K output tokens
Qwen3.5 Plus 2026-04-20 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.
| Specification | Google Gemini 3 Flash Preview | Qwen3.5 Plus 2026-04-20 |
|---|---|---|
| Maker | Qwen | |
| Weights | No public weights listed | No public weights listed |
| Released | December 17, 2025 | April 27, 2026 |
| Context window | 1.05M | 1M |
| Input $/Mtok | $0.50 | $0.30 |
| Output $/Mtok | $3.00 | $1.80 |
| Coding index | 43.7 | 39.5 |
| Independent measurements behind it | 2 | 2 |
| Cost per solved task | $0.37 | $1.35 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3 Flash Preview better than Qwen3.5 Plus 2026-04-20 for coding?
Pick Gemini 3 Flash Preview for coding: it scores 43.7 on the Vibe Coding Index against 39.5 for Qwen3.5 Plus 2026-04-20. Pick Qwen3.5 Plus 2026-04-20 for output tokens 1.7x cheaper ($1.80 vs $3.00 per million) and work measured by CaseLaw (Vals AI), where it leads.
Which is cheaper, Gemini 3 Flash Preview or Qwen3.5 Plus 2026-04-20?
Gemini 3 Flash Preview costs $0.50 per million input tokens and $3.00 per million output tokens; Qwen3.5 Plus 2026-04-20 costs $0.30 and $1.80. Per solved SWE-bench Verified task, Gemini 3 Flash Preview costs $0.37 and Qwen3.5 Plus 2026-04-20 $1.35.
Which has the bigger context window, Gemini 3 Flash Preview or Qwen3.5 Plus 2026-04-20?
Gemini 3 Flash Preview, with 1.05M tokens against 1M.
How many benchmarks is the Gemini 3 Flash Preview vs Qwen3.5 Plus 2026-04-20 comparison based on?
22 benchmarks have a result for both models as of October 22, 2026. Gemini 3 Flash Preview's coding index rests on 2 independent benchmarks and Qwen3.5 Plus 2026-04-20's on 2. Where only one model has a result, the page says so instead of naming a winner.