Compare / Claude Fable 5.1 vs Claude Opus 4.1
Claude Fable 5.1 vs Claude Opus 4.1
14 results from 3 sources that measured both models. Each row is in the source's own units; there is no overall winner.
| Benchmark | Metric | Claude Fable 5.1 | Claude Opus 4.1 |
|---|---|---|---|
| Arena (formerly LMArena)reported | OverallArena rating | 1,501 | 1,435 |
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,485 | 1,447 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,484 | 1,445 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,516 | 1,482 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,497 | 1,458 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,501 | 1,450 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,496 | 1,446 |
| Artificial Analysisreported | Artificial Analysis Intelligence Indexindex score | 53.4 | 22.8 |
| Artificial Analysisreported | GPQA Diamond% of questions | 93.7% | 80.9% |
| Artificial Analysisreported | Humanity's Last Exam% of questions | 59.1% | 12.5% |
| Artificial Analysisreported | Long-context reasoning (AA-LCR)% of questions | 85.3% | 76.0% |
| UGI Leaderboardreported | Requested-length error% off the requested word count | 3.0% | 3.0% |
| UGI Leaderboardreported | Style adherencescore from 0 to 1 | 0.43 | 0.38 |
| UGI Leaderboardreported | Writing scorescore out of 100 | 63.9 | 69.9 |
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.