Mistral Small 4 vs Qwen3.5 Plus 2026-04-20
Mistral Small 4 costs 3.0x less per output token than Qwen3.5 Plus 2026-04-20 ($0.60 vs $1.80 per million). Updated October 22, 2026; 4 benchmarks have a result for both.
Mistral Small 4 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; Mistral Small 4 has none, so the two cannot be ranked on coding.
Pick Mistral Small 4 for output tokens 3.0x cheaper ($0.60 vs $1.80 per million).
- Shared results
- 4
- Mistral Small 4 only
- 11
- Qwen3.5 Plus 2026-04-20 only
- 21
- Like-for-like categories
- 2 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
Intelligence
AA Intelligence Index
No call
Only Mistral Small 4 has a AA Intelligence Index result, 11.3.
Directional only
Agentic work
AA Agentic Index
No call
Only Mistral Small 4 has a AA Agentic Index result, 0.8.
Directional only
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
Qwen3.5 Plus 2026-04-20
Qwen3.5 Plus 2026-04-20 takes 1M tokens against 262K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Mistral Small 4
Mistral Small 4 $0.0004, 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
- Mistral Small 4 not benchmarked, Qwen3.5 Plus 2026-04-20 39.5 from 2 benchmarks.
- Widest category
- General, 12.7 points apart on average over 2 shared benchmarks.
- Widest single gap
- LMCA: Mistral Small 4 20.6% against Qwen3.5 Plus 2026-04-20 36.4%, 15.8 points apart on a 0 to 100 scale.
- Output price
- Mistral Small 4 $0.60 against Qwen3.5 Plus 2026-04-20 $1.80 per million output tokens, 3.0x apart.
- Context window
- Mistral Small 4 takes 262K 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 | Mistral Small 4 | Bars | Qwen3.5 Plus 2026-04-20 | Ties |
|---|---|---|---|---|
| Coding | 0 | 2 | ||
| General | 0 | 2 | ||
| All shared boards | 0 | 4 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index02
| Benchmark | Mistral Small 4 | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| AA Coding Index | 26.6 | Not measured | Only Mistral Small 4 measured |
| 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) | 0.0% | 15.7% | Qwen3.5 Plus 2026-04-20 |
| SciCode | 38.8% | Not measured | Only Mistral Small 4 measured |
| Terminal-Bench Hard (Artificial Analysis run) | 17.4% | Not measured | Only Mistral Small 4 measured |
| ALE-Bench | 497.6 | 608.9 | Qwen3.5 Plus 2026-04-20 |
| Neither model has a result on the other 36 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Mistral Small 4 | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| AA Intelligence Index | 11.3 | Not measured | Only Mistral Small 4 measured |
| Epoch Capabilities Index | Not measured | 146.2 | Only Qwen3.5 Plus 2026-04-20 measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index3 boards, none shared
| Benchmark | Mistral Small 4 | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| AA Agentic Index | 0.8 | Not measured | Only Mistral Small 4 measured |
| τ²-Bench Telecom | 41.2% | Not measured | Only Mistral Small 4 measured |
| Vending-Bench 2 | Not measured | $1 | Only Qwen3.5 Plus 2026-04-20 measured |
| Neither model has a result on the other 39 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Mistral Small 4 | 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 (Artificial Analysis run) | 76.9% | Not measured | Only Mistral Small 4 measured |
| Humanity's Last Exam (Artificial Analysis run) | 9.9% | Not measured | Only Mistral Small 4 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 |
| Kagi LLM Benchmark | 40.5% | Not measured | Only Mistral Small 4 measured |
| Neither model has a result on the other 15 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | Mistral Small 4 | 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 12 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | Mistral Small 4 | 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 13 boards here | |||
Web designNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Mistral Small 4 | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| Neither model has a result on 9 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Mistral Small 4 | Qwen3.5 Plus 2026-04-20 | Leader |
|---|---|---|---|
| SAGE (Vals AI) | Not measured | 30.4% | Only Qwen3.5 Plus 2026-04-20 measured |
| IFBench | 48.2% | Not measured | Only Mistral Small 4 measured |
| Long context reasoning (AA-LCR) | 49.7% | Not measured | Only Mistral Small 4 measured |
| DTBench | 70.9% | 80.5% | Qwen3.5 Plus 2026-04-20 |
| LMCA | 20.6% | 36.4% | Qwen3.5 Plus 2026-04-20 |
| 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 | Mistral Small 4 | 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
Mistral Small 4 costs less
Repository review
50K input + 3K output tokens
Mistral Small 4 costs less
Agent loop
200K input + 10K output tokens
Mistral Small 4 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 | Mistral Small 4 | Qwen3.5 Plus 2026-04-20 |
|---|---|---|
| Maker | Mistral AI | Qwen |
| Weights | Open weights | No public weights listed |
| Released | March 16, 2026 | April 27, 2026 |
| Context window | 262K | 1M |
| Input $/Mtok | $0.15 | $0.30 |
| Output $/Mtok | $0.60 | $1.80 |
| Coding index | Not benchmarked | 39.5 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | Not computable | $1.35 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Mistral Small 4 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; Mistral Small 4 has none, so the two cannot be ranked on coding. Pick Mistral Small 4 for output tokens 3.0x cheaper ($0.60 vs $1.80 per million).
Which is cheaper, Mistral Small 4 or Qwen3.5 Plus 2026-04-20?
Mistral Small 4 costs $0.15 per million input tokens and $0.60 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, Mistral Small 4 or Qwen3.5 Plus 2026-04-20?
Qwen3.5 Plus 2026-04-20, with 1M tokens against 262K.
How many benchmarks is the Mistral Small 4 vs Qwen3.5 Plus 2026-04-20 comparison based on?
4 benchmarks have a result for both models as of October 22, 2026. Mistral Small 4's coding index rests on 1 independent benchmark 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.