Compare / Claude Opus 5.5 vs GLM 5.1

Claude Opus 5.5 vs GLM 5.1

16 results from 5 sources that measured both models. Each row is in the source's own units; there is no overall winner.

Claude Opus 5.5
Anthropic · profile
GLM 5.1
Z.ai · profile
Results compared
16
Shared sources
5
BenchmarkMetricClaude Opus 5.5GLM 5.1
APEX-AgentsreportedTasks passed% of tasks 73.5%40.9%
Arena (formerly LMArena)reportedBusiness, management and financeArena rating 1,4991,465
Arena (formerly LMArena)reportedCreative writingArena rating 1,5211,448
Arena (formerly LMArena)reportedExpert promptsArena rating 1,5561,495
Arena (formerly LMArena)reportedInstruction followingArena rating 1,5161,460
Arena (formerly LMArena)reportedOverallArena rating 1,5091,465
Arena (formerly LMArena)reportedWriting, literature and languageArena rating 1,5201,453
Artificial AnalysisreportedArtificial Analysis Intelligence Indexindex score 57.626.1
Artificial AnalysisreportedHumanity's Last Exam% of questions 61.4%30.1%
Artificial AnalysisreportedLong-context reasoning (AA-LCR)% of questions 84.7%73.7%
Artificial AnalysisreportedSciCode% of problems 66.9%44.8%
Artificial AnalysisreportedTerminal-Bench 4.0% of tasks 59.6%2.0%
SimpleQA Verified (Epoch AI)reportedCorrect answers% of questions 72.2%34.0%
UGI LeaderboardreportedRequested-length error% off the requested word count 2.0%9.0%
UGI LeaderboardreportedStyle adherencescore from 0 to 1 0.430.38
UGI LeaderboardreportedWriting scorescore out of 100 70.061.7

Bold green marks the better value on that metric. Where a source reports ranges that overlap, the difference may not be meaningful; see the benchmark page for ranges.