Claude Fable 5.1 vs Qwen3.8-Max

  • Claude Fable 5.1 rates higher on LMArena’s text leaderboard: 1513 against 1484.
  • Qwen3.8-Max is cheaper: $2 / $6 per million input / output tokens, against $10 / $50 for Claude Fable 5.1.
  • On the 10 Vals AI benchmarks both have taken, Claude Fable 5.1 wins 9 and Qwen3.8-Max wins 1 (Claude Fable 5.1: Terminal-Bench 4.0, Vibe Code Bench, LiveCodeBench).
LMArena text rating over time
14701480149015001510Aug 2Aug 22Sep 11Oct 1Oct 22
LatestQwen3.8-Max 1484

Side by side

Models (2/6)
  • Claude Fable 5.1
  • Qwen3.8-Max
BenchmarkClaude Fable 5.1Qwen3.8-Max
The model
LabAnthropicAlibaba
Released2026-09-012026-09-03
WeightsProprietaryProprietary
Context window1M1M
Input, per 1M tokens$10$2
Output, per 1M tokens$50$6
LMArena, people’s votes
LMArena TextMillions of people compare two anonymous models side by side and vote for the better answer1513#3 of 3511484#15 of 351
LMArena WebDevPeople ask two anonymous models to build the same web app, try both and vote for the better one1743#5 of 1241673#12 of 124
LMArena VisionSide-by-side votes on prompts that include an image1320#4 of 1461313#10 of 146
LMArena CodingLMArena’s text votes on prompts that ask for code1531#7 of 3461503#21 of 346
LMArena MathLMArena’s text votes on math prompts1532#3 of 3391501#15 of 339
LMArena Creative writingLMArena’s text votes on stories, poems and other creative writing1510#3 of 3491477#16 of 349
LMArena Hard promptsLMArena’s text votes on the hardest prompts1528#3 of 3511497#16 of 351
LMArena Instruction followingLMArena’s text votes on prompts with specific instructions to follow1519#4 of 3511481#18 of 351
Vals AI, overall
Vals IndexVals AI’s headline score—59.05%#11 of 27
Vals AI, coding
Terminal-Bench 4.0Frontier-difficulty tasks an agent completes in a real terminal58.08%#5 of 5534.34%#18 of 55
SWE-benchReal GitHub issues from open-source projects—85.60%#16 of 85
Vibe Code BenchBuilding complete web apps from a plain-language brief, graded on whether the app works90.26%#6 of 11564.70%#49 of 115
Code MigrationRewriting working programs in a new language, graded on whether the new program still passes its tests—57.19%#10 of 28
LiveCodeBenchFresh competitive programming problems, collected after models’ training cut-offs to avoid contamination90.52%#1 of 14387.85%#10 of 143
Vals AI, finance
Finance AgentThe core tasks of a financial analyst, done as an agent with research tools—58.83%#23 of 31
Finance IndexVals AI’s composite of finance tasks—61.66%#5 of 31
Tax Agent BenchAgentic research into US corporate tax questions49.19%#2 of 7632.09%#22 of 76
Vals AI, law
Legal IndexVals AI’s composite of legal tasks—73.90%#5 of 28
Legal Research BenchAgentic US legal research55.29%#3 of 8546.15%#17 of 85
Vals AI, medicine
MedCodeAssigning the right medical billing codes from clinical notes53.51%#8 of 10740.67%#62 of 107
Vals AI, reasoning
GPQA DiamondGraduate-level questions in biology, physics and chemistry that experts answer well and search does not93.43%#9 of 13893.69%#6 of 138
MMLU-ProHarder, reasoning-focused multiple choice across 14 subjects, from law to engineering92.38%#1 of 13888.60%#18 of 138
MMMUCollege-level questions that need both an image and text90.64%#1 of 9388.03%#12 of 93
Terminal-Bench ScienceExpert-written scientific research workflows, run by an agent in a terminal40.00%#6 of 4212.86%#13 of 42

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Questions

Which is better, Claude Fable 5.1 or Qwen3.8-Max?

Claude Fable 5.1 rates higher on LMArena’s text leaderboard: 1513 against 1484. Qwen3.8-Max is cheaper: $2 / $6 per million input / output tokens, against $10 / $50 for Claude Fable 5.1. On the 10 Vals AI benchmarks both have taken, Claude Fable 5.1 wins 9 and Qwen3.8-Max wins 1 (Claude Fable 5.1: Terminal-Bench 4.0, Vibe Code Bench, LiveCodeBench).

Which is cheaper, Claude Fable 5.1 or Qwen3.8-Max?

Qwen3.8-Max is cheaper: $2 / $6 per million input / output tokens, against $10 / $50 for Claude Fable 5.1.

Sources

Every number on this page comes from these sources; models without a published number show none. Download the data. Cite as “Nexus Explorer, nexus.inc/models”.