Gemini 3.1 Pro Preview Custom Tools vs Qwen3.5 Plus 2026-04-20
Qwen3.5 Plus 2026-04-20 costs 6.7x less per output token than Gemini 3.1 Pro Preview Custom Tools ($1.80 vs $12.00 per million). Updated October 22, 2026; 1 benchmarks have a result for both.
Gemini 3.1 Pro Preview Custom Tools or Qwen3.5 Plus 2026-04-20: which to pick
Only Qwen3.5 Plus 2026-04-20 has a coding score, 39.5 on the Vibe Coding Index; Gemini 3.1 Pro Preview Custom Tools has none, so the two cannot be ranked on coding.
Pick Gemini 3.1 Pro Preview Custom Tools for a larger context window (1.05M against 1M tokens) and work measured by Vending-Bench 2, where it leads.
- Shared results
- 1
- Gemini 3.1 Pro Preview Custom Tools only
- 0
- Qwen3.5 Plus 2026-04-20 only
- 24
- Like-for-like categories
- 1 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
No call
Only Qwen3.5 Plus 2026-04-20 has a coding score, so no call is made.
One side not measured
Reasoning
GPQA Diamond
No call
Only Qwen3.5 Plus 2026-04-20 has a GPQA Diamond result, 87.4%.
Directional only
Math
AIME
No call
Only Qwen3.5 Plus 2026-04-20 has a AIME result, 86.0%.
Directional only
Knowledge
MMLU Pro
No call
Only Qwen3.5 Plus 2026-04-20 has a MMLU Pro result, 87.2%.
Directional only
Long documents
Listed context window
Gemini 3.1 Pro Preview Custom Tools
Gemini 3.1 Pro Preview Custom Tools takes 1.05M tokens against 1M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Qwen3.5 Plus 2026-04-20
Gemini 3.1 Pro Preview Custom Tools $0.0080, Qwen3.5 Plus 2026-04-20 $0.0012 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Qwen3.5 Plus 2026-04-20 has the number, $1.35.
Directional only
At a glance
- Coding index
- Gemini 3.1 Pro Preview Custom Tools not benchmarked, Qwen3.5 Plus 2026-04-20 39.5 from 2 benchmarks.
- Widest category
- Agentic work, 23.6 points apart on average over 1 shared benchmark.
- Widest single gap
- Vending-Bench 2: Gemini 3.1 Pro Preview Custom Tools $3,774 against Qwen3.5 Plus 2026-04-20 $1, 23.6 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.1 Pro Preview Custom Tools $12.00 against Qwen3.5 Plus 2026-04-20 $1.80 per million output tokens, 6.7x apart.
- Context window
- Gemini 3.1 Pro Preview Custom Tools 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 3.1 Pro Preview Custom Tools | Bars | Qwen3.5 Plus 2026-04-20 | Ties |
|---|---|---|---|---|
| Agentic work | 1 | 0 | ||
| All shared boards | 1 | 0 |
CodingDirectional onlySix of these boards feed the Vibe Coding Index4 boards, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| LiveCodeBench (Vals AI) | Not measured | 85.3% | Only Qwen3.5 Plus 2026-04-20 measured |
| SWE-bench Verified (Vals AI) | Not measured | 71.2% | Only Qwen3.5 Plus 2026-04-20 measured |
| Vibe Code Bench (Vals AI) | Not measured | 15.7% | Only Qwen3.5 Plus 2026-04-20 measured |
| ALE-Bench | Not measured | 608.9 | Only Qwen3.5 Plus 2026-04-20 measured |
| Neither model has a result on the other 35 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| Epoch Capabilities Index | Not measured | 146.2 | Only Qwen3.5 Plus 2026-04-20 measured |
| Neither model has a result on the other 1 board here | |||
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| Vending-Bench 2 | $3,774 | $1 | Gemini 3.1 Pro Preview Custom Tools |
| Neither model has a result on the other 40 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index5 boards, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 87.4% | Only Qwen3.5 Plus 2026-04-20 measured |
| MMMU Pro (Vals AI) | Not measured | 22.8% | Only Qwen3.5 Plus 2026-04-20 measured |
| GPQA Diamond (Epoch AI run) | Not measured | 84.8% | Only Qwen3.5 Plus 2026-04-20 measured |
| Chess puzzles | Not measured | 8.0% | Only Qwen3.5 Plus 2026-04-20 measured |
| Mystery game puzzles | Not measured | 17.0% | Only Qwen3.5 Plus 2026-04-20 measured |
| Neither model has a result on the other 17 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| AIME | Not measured | 86.0% | Only Qwen3.5 Plus 2026-04-20 measured |
| OTIS Mock AIME | Not measured | 86.7% | Only Qwen3.5 Plus 2026-04-20 measured |
| Neither model has a result on the other 11 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 87.2% | Only Qwen3.5 Plus 2026-04-20 measured |
| LegalBench (Vals AI) | Not measured | 85.1% | Only Qwen3.5 Plus 2026-04-20 measured |
| CaseLaw (Vals AI) | Not measured | 59.7% | Only Qwen3.5 Plus 2026-04-20 measured |
| CorpFin (Vals AI) | Not measured | 65.3% | Only Qwen3.5 Plus 2026-04-20 measured |
| MortgageTax (Vals AI) | Not measured | 60.8% | Only Qwen3.5 Plus 2026-04-20 measured |
| MedQA (Vals AI) | Not measured | 95.2% | Only Qwen3.5 Plus 2026-04-20 measured |
| SimpleQA Verified | Not measured | 25.4% | Only Qwen3.5 Plus 2026-04-20 measured |
| Neither model has a result on the other 11 boards here | |||
Web designNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| Neither model has a result on 9 boards here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index5 boards, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| SAGE (Vals AI) | Not measured | 30.4% | Only Qwen3.5 Plus 2026-04-20 measured |
| DTBench | Not measured | 80.5% | Only Qwen3.5 Plus 2026-04-20 measured |
| LMCA | Not measured | 36.4% | Only Qwen3.5 Plus 2026-04-20 measured |
| 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 41 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.1 Pro Preview Custom Tools | 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 3.1 Pro Preview Custom Tools | Qwen3.5 Plus 2026-04-20 |
|---|---|---|
| Maker | Qwen | |
| Weights | No public weights listed | No public weights listed |
| Released | February 25, 2026 | April 27, 2026 |
| Context window | 1.05M | 1M |
| Input $/Mtok | $2.00 | $0.30 |
| Output $/Mtok | $12.00 | $1.80 |
| Coding index | Not benchmarked | 39.5 |
| Independent measurements behind it | 0 | 2 |
| Cost per solved task | Not computable | $1.35 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.1 Pro Preview Custom Tools better than Qwen3.5 Plus 2026-04-20 for coding?
Only Qwen3.5 Plus 2026-04-20 has a coding score, 39.5 on the Vibe Coding Index; Gemini 3.1 Pro Preview Custom Tools has none, so the two cannot be ranked on coding. Pick Gemini 3.1 Pro Preview Custom Tools for a larger context window (1.05M against 1M tokens) and work measured by Vending-Bench 2, where it leads.
Which is cheaper, Gemini 3.1 Pro Preview Custom Tools or Qwen3.5 Plus 2026-04-20?
Gemini 3.1 Pro Preview Custom Tools costs $2.00 per million input tokens and $12.00 per million output tokens; Qwen3.5 Plus 2026-04-20 costs $0.30 and $1.80. Cost per solved task is known for Qwen3.5 Plus 2026-04-20 only.
Which has the bigger context window, Gemini 3.1 Pro Preview Custom Tools or Qwen3.5 Plus 2026-04-20?
Gemini 3.1 Pro Preview Custom Tools, with 1.05M tokens against 1M.
How many benchmarks is the Gemini 3.1 Pro Preview Custom Tools vs Qwen3.5 Plus 2026-04-20 comparison based on?
1 benchmarks have a result for both models as of October 22, 2026. Gemini 3.1 Pro Preview Custom Tools's coding index rests on 0 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.