Compare / Claude Sonnet 5.5 vs Grok 4.5

Claude Sonnet 5.5 vs Grok 4.5

7 results from 3 sources that measured both models. Each row is in the source's own units; there is no overall winner.

Claude Sonnet 5.5
Anthropic · profile
Grok 4.5
xAI · profile
Results compared
7
Shared sources
3
BenchmarkMetricClaude Sonnet 5.5Grok 4.5
APEX-AgentsreportedTasks passed% of tasks 75.5%56.2%
Artificial AnalysisreportedArtificial Analysis Intelligence Indexindex score 56.038.8
Artificial AnalysisreportedHumanity's Last Exam% of questions 55.0%42.7%
Artificial AnalysisreportedLong-context reasoning (AA-LCR)% of questions 82.7%79.3%
Artificial AnalysisreportedSciCode% of problems 61.0%55.0%
Artificial AnalysisreportedTerminal-Bench 4.0% of tasks 63.6%10.6%
SimpleQA Verified (Epoch AI)reportedCorrect answers% of questions 46.5%48.3%

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.