Claude Opus 5.5 vs Muse Wonder

  • Claude Opus 5.5 rates higher on LMArena’s text leaderboard: 1516 against 1501.
  • They cost about the same: $4 / $20 and $4 / $20 per million input / output tokens.
  • On the 10 Vals AI benchmarks both have taken, Claude Opus 5.5 wins 8 and Muse Wonder wins 2 (Claude Opus 5.5: Vals Index, Terminal-Bench 4.0, Vibe Code Bench).

Side by side

Models (2/6)
  • Claude Opus 5.5
  • Muse Wonder
BenchmarkClaude Opus 5.5Muse Wonder
The model
LabAnthropicMeta
Released2026-09-222026-10-12
WeightsProprietaryProprietary
Context window1M1M
Input, per 1M tokens$4$4
Output, per 1M tokens$20$20
LMArena, people’s votes
LMArena TextMillions of people compare two anonymous models side by side and vote for the better answer1516#2 of 3511501#7 of 351
LMArena WebDevPeople ask two anonymous models to build the same web app, try both and vote for the better one1807#1 of 1241651#18 of 124
LMArena VisionSide-by-side votes on prompts that include an image1321#2 of 146—
LMArena CodingLMArena’s text votes on prompts that ask for code1545#1 of 3461518#11 of 346
LMArena MathLMArena’s text votes on math prompts1518#6 of 3391484#30 of 339
LMArena Creative writingLMArena’s text votes on stories, poems and other creative writing1534#1 of 3491493#7 of 349
LMArena Hard promptsLMArena’s text votes on the hardest prompts1536#2 of 3511505#12 of 351
LMArena Instruction followingLMArena’s text votes on prompts with specific instructions to follow1539#1 of 3511493#10 of 351
Vals AI, overall
Vals IndexVals AI’s headline score70.18%#2 of 2764.88%#6 of 27
Vals AI, coding
Terminal-Bench 4.0Frontier-difficulty tasks an agent completes in a real terminal65.15%#1 of 5549.49%#10 of 55
Vibe Code BenchBuilding complete web apps from a plain-language brief, graded on whether the app works90.29%#5 of 11583.09%#20 of 115
Code MigrationRewriting working programs in a new language, graded on whether the new program still passes its tests81.01%#2 of 2872.36%#5 of 28
Vals AI, finance
Finance AgentThe core tasks of a financial analyst, done as an agent with research tools67.85%#1 of 3165.55%#6 of 31
Finance IndexVals AI’s composite of finance tasks65.59%#1 of 3161.23%#6 of 31
Tax Agent BenchAgentic research into US corporate tax questions45.57%#3 of 7636.27%#12 of 76
Vals AI, law
Legal IndexVals AI’s composite of legal tasks72.33%#7 of 2875.26%#3 of 28
Legal Research BenchAgentic US legal research50.48%#7 of 8550.48%#6 of 85
Vals AI, medicine
MedCodeAssigning the right medical billing codes from clinical notes49.80%#19 of 107—
Vals AI, reasoning
Terminal-Bench ScienceExpert-written scientific research workflows, run by an agent in a terminal47.14%#3 of 4222.86%#10 of 42

Add models in the compare tool. Vals Index: Claude Opus 5.5 70.18%, Muse Wonder 64.88%.

Questions

Which is better, Claude Opus 5.5 or Muse Wonder?

Claude Opus 5.5 rates higher on LMArena’s text leaderboard: 1516 against 1501. They cost about the same: $4 / $20 and $4 / $20 per million input / output tokens. On the 10 Vals AI benchmarks both have taken, Claude Opus 5.5 wins 8 and Muse Wonder wins 2 (Claude Opus 5.5: Vals Index, Terminal-Bench 4.0, Vibe Code Bench).

Which is cheaper, Claude Opus 5.5 or Muse Wonder?

They cost about the same: $4 / $20 and $4 / $20 per million input / output tokens.

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”.