Compare / Claude Opus 4.6 vs gpt-oss-120b
Claude Opus 4.6 vs gpt-oss-120b
12 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 Opus 4.6 | gpt-oss-120b |
|---|---|---|---|
| Arena (formerly LMArena)reported | OverallArena rating | 1,494 | 1,385 |
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,501 | 1,351 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,501 | 1,277 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,547 | 1,357 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,513 | 1,323 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,505 | 1,352 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,500 | 1,309 |
| UGI Leaderboardreported | Requested-length error% off the requested word count | 3.0% | 107.0% |
| UGI Leaderboardreported | Style adherencescore from 0 to 1 | 0.41 | 0.29 |
| UGI Leaderboardreported | Writing scorescore out of 100 | 70.9 | 38.5 |
| Vectara Hallucination Leaderboardreported | Answer rate% of documents | 99.8% | 99.9% |
| Vectara Hallucination Leaderboardreported | Hallucination rate% of summaries | 12.2% | 14.2% |
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.