Claude Opus 4.8 vs Qwen3.5-Flash
Claude Opus 4.8 leads Qwen3.5-Flash on coding, 65.0 to 41.1 on the Vibe Coding Index, and Qwen3.5-Flash costs 96.2x less per output token ($0.26 vs $25.00 per million). Updated October 22, 2026; 52 benchmarks have a result for both.
Claude Opus 4.8 or Qwen3.5-Flash: which to pick
Pick Claude Opus 4.8 for coding: it scores 65.0 on the Vibe Coding Index against 41.1 for Qwen3.5-Flash.
Pick Qwen3.5-Flash for output tokens 96.2x cheaper ($0.26 vs $25.00 per million) and a lower cost per solved task ($0.40 against $2.17).
- Shared results
- 52
- Claude Opus 4.8 only
- 84
- Qwen3.5-Flash 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
Claude Opus 4.8
Claude Opus 4.8 scores 65.0 against 41.1.
6 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
No call
Only Claude Opus 4.8 has a AA Intelligence Index result, 41.8.
Directional only
Agentic work
AA Agentic Index
No call
Only Claude Opus 4.8 has a AA Agentic Index result, 41.9.
Directional only
Reasoning
GPQA Diamond
Claude Opus 4.8
Claude Opus 4.8 leads, 92.4% against 82.8%.
Same board, both measured
Math
AIME
No call
Only Qwen3.5-Flash has a AIME result, 92.5%.
Directional only
Knowledge
MMLU Pro
Claude Opus 4.8
Claude Opus 4.8 leads, 89.6% against 84.1%.
Same board, both measured
Web design
Design Arena: websites
No call
Only Claude Opus 4.8 has a Design Arena: websites result, 1258.
Directional only
Long documents
Listed context window
No call
Both take 1M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Qwen3.5-Flash
Claude Opus 4.8 $0.018, Qwen3.5-Flash $0.0002 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Qwen3.5-Flash
Claude Opus 4.8 $2.17, Qwen3.5-Flash $0.40.
Published attempt cost and pass rate
At a glance
- Coding index
- Claude Opus 4.8 65.0 from 6 benchmarks, Qwen3.5-Flash 41.1 from 2 benchmarks.
- Widest category
- Coding, 27.9 points apart on average over 7 shared benchmarks.
- Widest single gap
- FrontierMath, tiers 1 to 3: Claude Opus 4.8 80.0% against Qwen3.5-Flash 18.2%, 61.8 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 4.8 $25.00 against Qwen3.5-Flash $0.26 per million output tokens, 96.2x apart.
- Context window
- Both take 1M tokens.
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 | Claude Opus 4.8 | Bars | Qwen3.5-Flash | Ties |
|---|---|---|---|---|
| Coding | 7 | 0 | ||
| Intelligence | 1 | 0 | ||
| Reasoning | 8 | 0 | ||
| Math | 4 | 0 | ||
| Knowledge | 10 | 1 | ||
| General | 21 | 0 | ||
| All shared boards | 51 | 1 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index70
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| LiveBench coding | 77.3% | Not measured | Only Claude Opus 4.8 measured |
| LMArena WebDev | 1556 | 1244 | Claude Opus 4.8 |
| AA Coding Index | 74.3 | Not measured | Only Claude Opus 4.8 measured |
| LiveCodeBench (Vals AI) | 87.8% | 83.3% | Claude Opus 4.8 |
| SWE-bench Verified (Vals AI) | 88.6% | 64.4% | Claude Opus 4.8 |
| Terminal-Bench 4 (Vals AI) | 23.2% | Not measured | Only Claude Opus 4.8 measured |
| Vibe Code Bench (Vals AI) | 82.7% | Not measured | Only Claude Opus 4.8 measured |
| Code migration (Vals AI) | 47.3% | Not measured | Only Claude Opus 4.8 measured |
| ProgramBench (Vals AI) | 1.0% | Not measured | Only Claude Opus 4.8 measured |
| Terminal-Bench 2.1 (Vals AI) | 71.9% | Not measured | Only Claude Opus 4.8 measured |
| SkillsBench (Vals AI) | 59.2% | Not measured | Only Claude Opus 4.8 measured |
| SciCode | 54.4% | Not measured | Only Claude Opus 4.8 measured |
| Terminal-Bench Hard (Artificial Analysis run) | 58.3% | Not measured | Only Claude Opus 4.8 measured |
| FrontierCode | 46.5% | Not measured | Only Claude Opus 4.8 measured |
| GSO-Bench | 47.1% | Not measured | Only Claude Opus 4.8 measured |
| WeirdML | 82.9% | Not measured | Only Claude Opus 4.8 measured |
| ALE-Bench | Not measured | 265.9 | Only Qwen3.5-Flash measured |
| LMArena Text: coding | 1490 | 1412 | Claude Opus 4.8 |
| LMArena Text: software and IT | 1488 | 1416 | Claude Opus 4.8 |
| LMArena WebDev: React | 1557 | 1229 | Claude Opus 4.8 |
| LMArena WebDev: HTML | 1543 | 1291 | Claude Opus 4.8 |
| SciCode | 12.3% | Not measured | Only Claude Opus 4.8 measured |
| SWE Atlas: Codebase QnA | 57.3% | Not measured | Only Claude Opus 4.8 measured |
| SWE Atlas: Refactoring | 46.7% | Not measured | Only Claude Opus 4.8 measured |
| SWE Atlas: Test Writing | 49.6% | Not measured | Only Claude Opus 4.8 measured |
| Neither model has a result on the other 18 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | 41.8 | Not measured | Only Claude Opus 4.8 measured |
| Epoch Capabilities Index | 159.0 | 143.5 | Claude Opus 4.8 |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index28 boards, none shared
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| AA Agentic Index | 41.9 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: agents building web apps | 1233 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: agents building full-stack apps | 1249 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: agents building mobile apps | 1222 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: agents building Android apps | 1231 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: agents building Godot games | 1231 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: agents building games | 1238 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: HTML slides | 1160 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: PowerPoint slides | 1201 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: spreadsheets | 1314 | Not measured | Only Claude Opus 4.8 measured |
| LiveBench research | 81.8% | Not measured | Only Claude Opus 4.8 measured |
| LiveBench browser | 96.0% | Not measured | Only Claude Opus 4.8 measured |
| LiveBench long agentic | 48.3% | Not measured | Only Claude Opus 4.8 measured |
| Finance Agent (Vals AI) | 53.9% | Not measured | Only Claude Opus 4.8 measured |
| Tax Agent Bench (Vals AI) | 30.0% | Not measured | Only Claude Opus 4.8 measured |
| Legal Research Bench (Vals AI) | 43.8% | Not measured | Only Claude Opus 4.8 measured |
| Excel Modeling Benchmark (Vals AI) | 69.4% | Not measured | Only Claude Opus 4.8 measured |
| Terminal-Bench-Science (Vals AI) | 4.3% | Not measured | Only Claude Opus 4.8 measured |
| Time Horizon Index (Vals AI) | 11.8% | Not measured | Only Claude Opus 4.8 measured |
| τ²-Bench Telecom | 94.4% | Not measured | Only Claude Opus 4.8 measured |
| APEX-Agents | 48.9% | Not measured | Only Claude Opus 4.8 measured |
| Remote Labor Index | 8.3% | Not measured | Only Claude Opus 4.8 measured |
| OSWorld 2.0 | 20.6% | Not measured | Only Claude Opus 4.8 measured |
| DeepResearch Bench | 50.2% | Not measured | Only Claude Opus 4.8 measured |
| PostTrainBench | 33.8% | Not measured | Only Claude Opus 4.8 measured |
| Vending-Bench 2 | $5,787 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Search | 1204 | Not measured | Only Claude Opus 4.8 measured |
| MCP Atlas | 82.2% | Not measured | Only Claude Opus 4.8 measured |
| Neither model has a result on the other 14 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index80
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| GPQA Diamond | 92.4% | 82.8% | Claude Opus 4.8 |
| LiveBench reasoning | 89.2% | Not measured | Only Claude Opus 4.8 measured |
| MMMU Pro (Vals AI) | 86.6% | 81.9% | Claude Opus 4.8 |
| GPQA Diamond (Artificial Analysis run) | 92.0% | Not measured | Only Claude Opus 4.8 measured |
| Humanity's Last Exam (Artificial Analysis run) | 48.7% | Not measured | Only Claude Opus 4.8 measured |
| GPQA Diamond (Epoch AI run) | 91.0% | 82.3% | Claude Opus 4.8 |
| ARC-AGI | 92.5% | Not measured | Only Claude Opus 4.8 measured |
| ARC-AGI-2 | 72.1% | Not measured | Only Claude Opus 4.8 measured |
| SimpleBench | 64.8% | Not measured | Only Claude Opus 4.8 measured |
| Chess puzzles | 52.0% | 14.0% | Claude Opus 4.8 |
| Mystery game puzzles | 36.0% | 20.0% | Claude Opus 4.8 |
| EBR-bench | 28.6% | Not measured | Only Claude Opus 4.8 measured |
| LMArena Text: hard prompts | 1482 | 1403 | Claude Opus 4.8 |
| LMArena Text: expert | 1503 | 1407 | Claude Opus 4.8 |
| LMArena Text: hard prompts in English | 1487 | 1409 | Claude Opus 4.8 |
| LMArena Vision: diagrams | 1315 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Vision: homework | 1337 | Not measured | Only Claude Opus 4.8 measured |
| Kagi LLM Benchmark | 88.8% | Not measured | Only Claude Opus 4.8 measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| AIME | Not measured | 92.5% | Only Qwen3.5-Flash measured |
| OTIS Mock AIME | 98.3% | 84.4% | Claude Opus 4.8 |
| FrontierMath, tiers 1 to 3 | 80.0% | 18.2% | Claude Opus 4.8 |
| FrontierMath, tier 4 | 56.1% | Not measured | Only Claude Opus 4.8 measured |
| ProofBench | 69.0% | Not measured | Only Claude Opus 4.8 measured |
| LMArena Text: math | 1486 | 1407 | Claude Opus 4.8 |
| LMArena Text: mathematical work | 1497 | 1413 | Claude Opus 4.8 |
| MathArena | 39.8% | Not measured | Only Claude Opus 4.8 measured |
| Neither model has a result on the other 6 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index101
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| MMLU Pro | 89.6% | 84.1% | Claude Opus 4.8 |
| LegalBench (Vals AI) | 83.6% | 84.3% | Qwen3.5-Flash |
| CaseLaw (Vals AI) | Not measured | 56.0% | Only Qwen3.5-Flash measured |
| CorpFin (Vals AI) | 66.7% | 63.6% | Claude Opus 4.8 |
| TaxEval (Vals AI) | 75.6% | 72.2% | Claude Opus 4.8 |
| MortgageTax (Vals AI) | 69.9% | 67.4% | Claude Opus 4.8 |
| MedCode (Vals AI) | 53.2% | 33.0% | Claude Opus 4.8 |
| SimpleQA Verified | 53.0% | 20.3% | Claude Opus 4.8 |
| LMArena Text: science | 1477 | 1415 | Claude Opus 4.8 |
| LMArena Text: medicine and healthcare | 1464 | 1407 | Claude Opus 4.8 |
| LMArena Text: legal and government | 1477 | 1398 | Claude Opus 4.8 |
| LMArena Text: business and finance | 1458 | 1394 | Claude Opus 4.8 |
| FACTS Benchmark Suite | 53.5% | Not measured | Only Claude Opus 4.8 measured |
| Neither model has a result on the other 7 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| Design Arena: websites | 1258 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: UI components | 1255 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: game dev | 1264 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: data viz | 1240 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: 3D | 1222 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: all code categories | 1255 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: SVG | 1194 | Not measured | Only Claude Opus 4.8 measured |
| Design Arena: ASCII art | 1277 | Not measured | Only Claude Opus 4.8 measured |
| LiveBench design | 78.8% | Not measured | Only Claude Opus 4.8 measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index210
| Benchmark | Claude Opus 4.8 | Qwen3.5-Flash | Leader |
|---|---|---|---|
| LiveBench data analysis | 66.0% | Not measured | Only Claude Opus 4.8 measured |
| Public Benefits Bench (Vals AI) | 68.1% | Not measured | Only Claude Opus 4.8 measured |
| SAGE (Vals AI) | 54.8% | 42.5% | Claude Opus 4.8 |
| MedScribe (Vals AI) | 85.8% | 70.6% | Claude Opus 4.8 |
| Vals Multimodal Index | 70.9% | Not measured | Only Claude Opus 4.8 measured |
| IFBench | 62.2% | Not measured | Only Claude Opus 4.8 measured |
| Long context reasoning (AA-LCR) | 77.7% | Not measured | Only Claude Opus 4.8 measured |
| DTBench | 94.9% | 82.9% | Claude Opus 4.8 |
| LMCA | 57.5% | 29.1% | Claude Opus 4.8 |
| Surface Evolver Bench | 87.5% | Not measured | Only Claude Opus 4.8 measured |
| Furniture assembly | 42.5% | Not measured | Only Claude Opus 4.8 measured |
| LMArena Text | 1461 | 1397 | Claude Opus 4.8 |
| LMArena Text: instruction following | 1476 | 1374 | Claude Opus 4.8 |
| LMArena Text: creative writing | 1454 | 1343 | Claude Opus 4.8 |
| LMArena Vision | 1294 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Text: English | 1468 | 1404 | Claude Opus 4.8 |
| LMArena Text: non-English | 1450 | 1385 | Claude Opus 4.8 |
| LMArena Text: Chinese | 1506 | 1445 | Claude Opus 4.8 |
| LMArena Text: German | 1472 | 1390 | Claude Opus 4.8 |
| LMArena Text: Japanese | 1442 | 1369 | Claude Opus 4.8 |
| LMArena Text: Korean | 1431 | 1344 | Claude Opus 4.8 |
| LMArena Text: French | 1481 | 1413 | Claude Opus 4.8 |
| LMArena Text: Spanish | 1465 | 1400 | Claude Opus 4.8 |
| LMArena Text: Russian | 1474 | 1380 | Claude Opus 4.8 |
| LMArena Text: Polish | 1459 | 1376 | Claude Opus 4.8 |
| LMArena Text: multi-turn | 1476 | 1393 | Claude Opus 4.8 |
| LMArena Text: longer queries | 1483 | 1392 | Claude Opus 4.8 |
| LMArena Text: writing and language | 1461 | 1369 | Claude Opus 4.8 |
| LMArena Text: entertainment and media | 1440 | 1347 | Claude Opus 4.8 |
| LMArena Vision: English | 1293 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Vision: Chinese | 1346 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Vision: reading text | 1303 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Vision: humor | 1282 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Vision: creative writing | 1301 | Not measured | Only Claude Opus 4.8 measured |
| LMArena Document | 1475 | Not measured | Only Claude Opus 4.8 measured |
| EQ-Bench 4 | 1281 | Not measured | Only Claude Opus 4.8 measured |
| Neither model has a result on the other 12 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 4.8 | 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
Qwen3.5-Flash costs less
Repository review
50K input + 3K output tokens
Qwen3.5-Flash costs less
Agent loop
200K input + 10K output tokens
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.
| Specification | Anthropic Claude Opus 4.8 | Qwen3.5-Flash |
|---|---|---|
| Maker | Anthropic | Qwen |
| Weights | No public weights listed | No public weights listed |
| Released | May 27, 2026 | February 25, 2026 |
| Context window | 1M | 1M |
| Input $/Mtok | $5.00 | $0.065 |
| Output $/Mtok | $25.00 | $0.26 |
| Coding index | 65.0 | 41.1 |
| Independent measurements behind it | 6 | 2 |
| Cost per solved task | $2.17 | $0.40 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 4.8 better than Qwen3.5-Flash for coding?
Pick Claude Opus 4.8 for coding: it scores 65.0 on the Vibe Coding Index against 41.1 for Qwen3.5-Flash. Pick Qwen3.5-Flash for output tokens 96.2x cheaper ($0.26 vs $25.00 per million) and a lower cost per solved task ($0.40 against $2.17).
Which is cheaper, Claude Opus 4.8 or Qwen3.5-Flash?
Claude Opus 4.8 costs $5.00 per million input tokens and $25.00 per million output tokens; Qwen3.5-Flash costs $0.065 and $0.26. Per solved SWE-bench Verified task, Claude Opus 4.8 costs $2.17 and Qwen3.5-Flash $0.40.
Which has the bigger context window, Claude Opus 4.8 or Qwen3.5-Flash?
Neither: both take 1M tokens.
How many benchmarks is the Claude Opus 4.8 vs Qwen3.5-Flash comparison based on?
52 benchmarks have a result for both models as of October 22, 2026. Claude Opus 4.8's coding index rests on 6 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.