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Claude Fable 5.1 vs Qwen3.5 397B A17B

Updated October 21, 2026. 59 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.

Claude Fable 5.1Anthropic
Coding
89.1
Overall
53.4
Output $/M
$50.00
59
Qwen3.5 397B A17BQwen
Coding
28.6
Overall
21.4
Output $/M
$2.34
0
vs boards won of 59 shared

Decision reading

Pick Claude Fable 5.1 for coding: it scores 89.1 on the Vibe Coding Index against 28.6 for Qwen3.5 397B A17B.

Pick Qwen3.5 397B A17B when output tokens cost 21.4x less.

Shared results
59
Claude Fable 5.1 only
65
Qwen3.5 397B A17B only
6
Like-for-like categories
8 of 9

Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.

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.

At a glance

Coding index
Claude Fable 5.1 89.1 from 2 benchmarks, Qwen3.5 397B A17B 28.6 from 1 benchmark.
Widest category
Agentic work, 43.7 points apart on average over 1 shared benchmark.
Widest single gap
FrontierMath, tiers 1 to 3: Claude Fable 5.1 90.2% against Qwen3.5 397B A17B 31.2%, 58.9 points apart on a 0 to 100 scale.
Output price
Claude Fable 5.1 $50.00 against Qwen3.5 397B A17B $2.34 per million output tokens, 21.4x apart.
Context window
Claude Fable 5.1 takes 1M tokens, Qwen3.5 397B A17B 262K.

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
CategoryClaude Fable 5.1BarsQwen3.5 397B A17BTies
Coding70
Intelligence20
Agentic work10
Reasoning80
Math40
Knowledge40
Web design70
General260
All shared boards590
CodingLike-for-likeFour of these boards feed the Vibe Coding Index70
Coding benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
LiveBench coding97.7%Not measuredOnly Claude Fable 5.1 measured
LMArena WebDev17431400Claude Fable 5.1
AA Coding Index81.6Not measuredOnly Claude Fable 5.1 measured
LiveCodeBench (Vals AI)90.5%Not measuredOnly Claude Fable 5.1 measured
Terminal-Bench 4 (Vals AI)58.1%Not measuredOnly Claude Fable 5.1 measured
Vibe Code Bench (Vals AI)90.3%Not measuredOnly Claude Fable 5.1 measured
Code migration (Vals AI)54.6%Not measuredOnly Claude Fable 5.1 measured
ProgramBench (Vals AI)7.0%Not measuredOnly Claude Fable 5.1 measured
IOI (Vals AI)90.8%Not measuredOnly Claude Fable 5.1 measured
Terminal-Bench 2.1 (Vals AI)85.0%Not measuredOnly Claude Fable 5.1 measured
SWE-bench Multimodal (Vals AI)61.3%Not measuredOnly Claude Fable 5.1 measured
Vibe Code Bench 1-100 (Vals AI)28.0%Not measuredOnly Claude Fable 5.1 measured
SkillsBench (Vals AI)61.5%Not measuredOnly Claude Fable 5.1 measured
CyberBench (Vals AI)70.4%Not measuredOnly Claude Fable 5.1 measured
SciCode63.1%44.8%Claude Fable 5.1
Terminal-Bench Hard (Artificial Analysis run)Not measured40.9%Only Qwen3.5 397B A17B measured
FrontierCode50.9%Not measuredOnly Claude Fable 5.1 measured
FrontierSWE56.3%Not measuredOnly Claude Fable 5.1 measured
GSO-Bench88.2%Not measuredOnly Claude Fable 5.1 measured
WeirdML92.9%Not measuredOnly Claude Fable 5.1 measured
MirrorCode73.3%Not measuredOnly Claude Fable 5.1 measured
ALE-Bench2143.2621.9Claude Fable 5.1
LMArena Text: coding15321464Claude Fable 5.1
LMArena Text: software and IT15301463Claude Fable 5.1
LMArena WebDev: React17921388Claude Fable 5.1
LMArena WebDev: HTML16841410Claude Fable 5.1
LMArena WebDev: from an image1722Not measuredOnly Claude Fable 5.1 measured
Neither model has a result on the other 11 boards here
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
Intelligence benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
AA Intelligence Index53.421.4Claude Fable 5.1
Epoch Capabilities Index166.5146.8Claude Fable 5.1
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
Agentic work benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
AA Agentic Index57.9Not measuredOnly Claude Fable 5.1 measured
Design Arena: agents building web apps1318Not measuredOnly Claude Fable 5.1 measured
Design Arena: agents building full-stack apps1326Not measuredOnly Claude Fable 5.1 measured
Design Arena: agents building mobile apps1267Not measuredOnly Claude Fable 5.1 measured
Design Arena: agents building Godot games1327Not measuredOnly Claude Fable 5.1 measured
Design Arena: PowerPoint slides1328Not measuredOnly Claude Fable 5.1 measured
Design Arena: spreadsheets1374Not measuredOnly Claude Fable 5.1 measured
LiveBench research82.0%Not measuredOnly Claude Fable 5.1 measured
LiveBench browser100.0%Not measuredOnly Claude Fable 5.1 measured
LiveBench long agentic80.8%Not measuredOnly Claude Fable 5.1 measured
SREBench (Vals AI)22.9%Not measuredOnly Claude Fable 5.1 measured
Finance Agent (Vals AI)58.9%Not measuredOnly Claude Fable 5.1 measured
Tax Agent Bench (Vals AI)49.2%Not measuredOnly Claude Fable 5.1 measured
Legal Research Bench (Vals AI)55.3%Not measuredOnly Claude Fable 5.1 measured
Excel Modeling Benchmark (Vals AI)76.7%Not measuredOnly Claude Fable 5.1 measured
Terminal-Bench-Science (Vals AI)40.0%Not measuredOnly Claude Fable 5.1 measured
Time Horizon Index (Vals AI)63.3%Not measuredOnly Claude Fable 5.1 measured
CUA-bench (Vals AI)13.2%Not measuredOnly Claude Fable 5.1 measured
Robo-bench (Vals AI)5.8%Not measuredOnly Claude Fable 5.1 measured
τ²-Bench TelecomNot measured95.6%Only Qwen3.5 397B A17B measured
APEX-Agents68.6%24.9%Claude Fable 5.1
Remote Labor Index17.9%Not measuredOnly Claude Fable 5.1 measured
SpireClimb2.0%Not measuredOnly Claude Fable 5.1 measured
Vending-Bench 2$5,422Not measuredOnly Claude Fable 5.1 measured
LMArena Search1246Not measuredOnly Claude Fable 5.1 measured
Neither model has a result on the other 14 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index80
Reasoning benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
GPQA Diamond93.4%Not measuredOnly Claude Fable 5.1 measured
LiveBench reasoning91.7%Not measuredOnly Claude Fable 5.1 measured
MysteryMechanism (Vals AI)47.8%Not measuredOnly Claude Fable 5.1 measured
MMMU Pro (Vals AI)90.6%Not measuredOnly Claude Fable 5.1 measured
GPQA Diamond (Artificial Analysis run)93.7%89.3%Claude Fable 5.1
Humanity's Last Exam (Artificial Analysis run)59.1%29.0%Claude Fable 5.1
GPQA Diamond (Epoch AI run)Not measured86.4%Only Qwen3.5 397B A17B measured
ARC-AGI97.5%Not measuredOnly Claude Fable 5.1 measured
ARC-AGI-290.0%Not measuredOnly Claude Fable 5.1 measured
Chess puzzles48.0%Not measuredOnly Claude Fable 5.1 measured
Mystery game puzzles58.0%18.0%Claude Fable 5.1
EBR-bench57.1%Not measuredOnly Claude Fable 5.1 measured
LMArena Text: hard prompts15281448Claude Fable 5.1
LMArena Text: expert15441462Claude Fable 5.1
LMArena Text: hard prompts in English15221450Claude Fable 5.1
LMArena Vision: diagrams13431277Claude Fable 5.1
LMArena Vision: homework13451292Claude Fable 5.1
Neither model has a result on the other 4 boards here
MathLike-for-likePublic boards, shown as published, kept out of the index40
Math benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
OTIS Mock AIME100.0%88.9%Claude Fable 5.1
FrontierMath, tiers 1 to 390.2%31.2%Claude Fable 5.1
FrontierMath, tier 487.8%Not measuredOnly Claude Fable 5.1 measured
ProofBench100.0%Not measuredOnly Claude Fable 5.1 measured
LMArena Text: math15311453Claude Fable 5.1
LMArena Text: mathematical work15411454Claude Fable 5.1
Neither model has a result on the other 7 boards here
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index40
Knowledge benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
MMLU Pro92.4%Not measuredOnly Claude Fable 5.1 measured
LegalBench (Vals AI)88.5%Not measuredOnly Claude Fable 5.1 measured
TaxEval (Vals AI)76.0%Not measuredOnly Claude Fable 5.1 measured
MortgageTax (Vals AI)70.8%Not measuredOnly Claude Fable 5.1 measured
MedCode (Vals AI)53.5%Not measuredOnly Claude Fable 5.1 measured
SimpleQA Verified70.8%Not measuredOnly Claude Fable 5.1 measured
LMArena Text: science15321457Claude Fable 5.1
LMArena Text: medicine and healthcare15311455Claude Fable 5.1
LMArena Text: legal and government15141441Claude Fable 5.1
LMArena Text: business and finance14931435Claude Fable 5.1
Neither model has a result on the other 7 boards here
Web designLike-for-likePublic boards, shown as published, kept out of the index70
Web design benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
Design Arena: websites13131191Claude Fable 5.1
Design Arena: UI components13381163Claude Fable 5.1
Design Arena: game dev13821141Claude Fable 5.1
Design Arena: data viz13441175Claude Fable 5.1
Design Arena: 3D13931161Claude Fable 5.1
Design Arena: all code categories13361180Claude Fable 5.1
Design Arena: SVG13011139Claude Fable 5.1
Design Arena: ASCII art1324Not measuredOnly Claude Fable 5.1 measured
LiveBench design83.4%Not measuredOnly Claude Fable 5.1 measured
GeneralLike-for-likePublic boards, shown as published, kept out of the index260
General benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
LiveBench data analysis80.3%Not measuredOnly Claude Fable 5.1 measured
Public Benefits Bench (Vals AI)74.9%Not measuredOnly Claude Fable 5.1 measured
SAGE (Vals AI)48.5%Not measuredOnly Claude Fable 5.1 measured
MedScribe (Vals AI)91.3%Not measuredOnly Claude Fable 5.1 measured
IFBenchNot measured78.8%Only Qwen3.5 397B A17B measured
Long context reasoning (AA-LCR)85.3%77.3%Claude Fable 5.1
DTBench97.6%87.5%Claude Fable 5.1
LMCA65.5%37.9%Claude Fable 5.1
Furniture assembly70.0%Not measuredOnly Claude Fable 5.1 measured
LMArena Text15121437Claude Fable 5.1
LMArena Text: instruction following15181424Claude Fable 5.1
LMArena Text: creative writing15091402Claude Fable 5.1
LMArena Vision13191262Claude Fable 5.1
LMArena Text: English15061443Claude Fable 5.1
LMArena Text: non-English15081430Claude Fable 5.1
LMArena Text: Chinese15841498Claude Fable 5.1
LMArena Text: German14991445Claude Fable 5.1
LMArena Text: Japanese15621429Claude Fable 5.1
LMArena Text: Korean15171384Claude Fable 5.1
LMArena Text: French15231462Claude Fable 5.1
LMArena Text: Spanish15201441Claude Fable 5.1
LMArena Text: Russian15201430Claude Fable 5.1
LMArena Text: Polish15251447Claude Fable 5.1
LMArena Text: multi-turn14931446Claude Fable 5.1
LMArena Text: longer queries15241441Claude Fable 5.1
LMArena Text: writing and language15101415Claude Fable 5.1
LMArena Text: entertainment and media14971399Claude Fable 5.1
LMArena Vision: English13131268Claude Fable 5.1
LMArena Vision: Chinese13911314Claude Fable 5.1
LMArena Vision: reading text13271271Claude Fable 5.1
LMArena Vision: humor13181262Claude Fable 5.1
LMArena Vision: captioningNot measured1230Only Qwen3.5 397B A17B measured
LMArena Vision: recognizing thingsNot measured1265Only Qwen3.5 397B A17B measured
LMArena Vision: creative writing13301260Claude Fable 5.1
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
Image generation benchmarks for Claude Fable 5.1 and Qwen3.5 397B A17B
BenchmarkClaude Fable 5.1Qwen3.5 397B A17BLeader
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

Claude Fable 5.1$0.035Fits in one request
Qwen3.5 397B A17B$0.0016Fits in one request

Qwen3.5 397B A17B costs less

Repository review

50K input + 3K output tokens

Claude Fable 5.1$0.650Fits in one request
Qwen3.5 397B A17B$0.027Fits in one request

Qwen3.5 397B A17B costs less

Agent loop

200K input + 10K output tokens

Claude Fable 5.1$2.50Fits in one request
Qwen3.5 397B A17B$0.101Fits in one request

Qwen3.5 397B A17B 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 Claude Fable 5.1 and Qwen3.5 397B A17B
SpecificationAnthropic Claude Fable 5.1Qwen3.5 397B A17B
MakerAnthropicQwen
WeightsNo public weights listedOpen weights
ReleasedSeptember 1, 2026February 16, 2026
Context window1M262K
Input $/Mtok$10.00$0.39
Output $/Mtok$50.00$2.34
Coding index89.128.6
Independent measurements behind it21
Cost per solved taskNot computableNot computable
SourceOpenRouter listingOpenRouter listing

Questions

Is Claude Fable 5.1 better than Qwen3.5 397B A17B for coding?

Pick Claude Fable 5.1 for coding: it scores 89.1 on the Vibe Coding Index against 28.6 for Qwen3.5 397B A17B. Pick Qwen3.5 397B A17B when output tokens cost 21.4x less.

Which is cheaper, Claude Fable 5.1 or Qwen3.5 397B A17B?

Claude Fable 5.1 costs $10.00 per million input tokens and $50.00 per million output tokens; Qwen3.5 397B A17B costs $0.39 and $2.34. Cost per solved task is known for neither of them.

Which has the bigger context window, Claude Fable 5.1 or Qwen3.5 397B A17B?

Claude Fable 5.1, with 1M tokens against 262K.

How many benchmarks is the Claude Fable 5.1 vs Qwen3.5 397B A17B comparison based on?

59 benchmarks have a result for both models as of October 21, 2026. Claude Fable 5.1's coding index rests on 2 independent benchmarks and Qwen3.5 397B A17B's on 1. Where only one model has a result, the page says so instead of naming a winner.

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