Compare / Claude Opus 4.8 vs Grok 4.5
Claude Opus 4.8 vs Grok 4.5
18 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 4.8 | Grok 4.5 |
|---|---|---|---|
| Arena (formerly LMArena)reported | Confirmed task successIPS effect estimate | 0.04 | -0.01 |
| Arena (formerly LMArena)reported | Praise over complaintIPS effect estimate | 0.15 | -0.03 |
| Arena (formerly LMArena)reported | SteerabilityIPS effect estimate | 0.10 | 0.04 |
| Arena (formerly LMArena)reported | Tool groundingIPS effect estimate | -0.00 | 0.00 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,486 | 1,464 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,195 | 1,202 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,469 | 1,465 |
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,490 | 1,465 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,467 | 1,452 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,525 | 1,488 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,491 | 1,462 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,480 | 1,465 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,474 | 1,459 |
| tau2-benchreported | Consistency (pass^4)% of tasks | 22.7% | 32.0% |
| tau2-benchreported | Task success (pass^1)% of tasks | 39.7% | 47.9% |
| UGI Leaderboardreported | Requested-length error% off the requested word count | 6.0% | 21.0% |
| UGI Leaderboardreported | Style adherencescore from 0 to 1 | 0.40 | 0.32 |
| UGI Leaderboardreported | Writing scorescore out of 100 | 65.9 | 60.0 |
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.