Compare / Claude Haiku 4.5 vs Claude Opus 4.5
Claude Haiku 4.5 vs Claude Opus 4.5
21 results from 4 sources that measured both models. Each row is in the source's own units; there is no overall winner.
| Benchmark | Metric | Claude Haiku 4.5 | Claude Opus 4.5 |
|---|---|---|---|
| Arena (formerly LMArena)reported | OverallArena rating | 1,419 | 1,465 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,418 | 1,459 |
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,420 | 1,472 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,387 | 1,469 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,452 | 1,503 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,415 | 1,483 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,414 | 1,474 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,399 | 1,467 |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Irrelevance detection% correct | 95.3% | 90.8% |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Memory% correct | 54.4% | 73.8% |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Multi-turn tasks% correct | 53.6% | 68.4% |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Overall accuracy% correct | 68.7% | 77.5% |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Relevance detection% correct | 62.5% | 68.8% |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Single-turn calls (curated)% correct | 86.5% | 89.7% |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Single-turn calls (user-contributed)% correct | 78.7% | 79.8% |
| Berkeley Function Calling Leaderboard (BFCL) V4reported | Web search% correct | 83.5% | 84.5% |
| UGI Leaderboardreported | Requested-length error% off the requested word count | 6.0% | 3.0% |
| UGI Leaderboardreported | Style adherencescore from 0 to 1 | 0.39 | 0.39 |
| UGI Leaderboardreported | Writing scorescore out of 100 | 52.2 | 70.4 |
| Vectara Hallucination Leaderboardreported | Answer rate% of documents | 99.5% | 98.7% |
| Vectara Hallucination Leaderboardreported | Hallucination rate% of summaries | 9.8% | 10.9% |
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.