Compare / Claude Opus 5.5 vs Gemini 3.5 Flash
Claude Opus 5.5 vs Gemini 3.5 Flash
9 results from 2 sources that measured both models. Each row is in the source's own units; there is no overall winner.
| Benchmark | Metric | Claude Opus 5.5 | Gemini 3.5 Flash |
|---|---|---|---|
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,499 | 1,468 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,521 | 1,466 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,556 | 1,491 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,516 | 1,465 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,509 | 1,477 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,520 | 1,472 |
| UGI Leaderboardreported | Requested-length error% off the requested word count | 2.0% | 9.0% |
| UGI Leaderboardreported | Style adherencescore from 0 to 1 | 0.43 | 0.35 |
| UGI Leaderboardreported | Writing scorescore out of 100 | 70.0 | 72.5 |
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.