Claude Opus 4.1
ECI#88
144Claude Opus 4.1 is a closed-weights model from Anthropic, released August 5, 2025. It has an ECI score of 144 and ranks 88th of 253 tracked models. At the time of its release, it ranked 7th of 156 tracked models.
Claude Opus 4.1 vs select alternatives
| Domain | Benchmark | Claude Opus 4.1 | |||
|---|---|---|---|---|---|
ECI scoreBest score 167 | 144 | 143 | 144 | 145 | |
| Ranking | #88 | #96 | #91 | #81 | |
| Games | Chess PuzzlesBest score 72% | ||||
Mystery Game PuzzlesBest score 84% | |||||
| Mathematics | FrontierMath Tiers 1-3 (v2)Best score 94% | ||||
FrontierMath Tier 4 (v2)Best score 100% | |||||
OTIS Mock AIME 2024-2025Best score 100% | |||||
| Science | Humanity's Last ExamBest score 55% | ||||
GPQA DiamondBest score 96% | |||||
| Software engineering | METR Time HorizonsBest score 17 hr 25 min | 1 hr 54 min | 1 hr 40 min | — | 38 min 44 sec |
SWE-bench VerifiedBest score 83% |
