Overall
Epoch Capabilities Index
34 models with a published score, best first. Higher is better. The record has been broken 11 times since Oct 22, 2024.
169Claude Opus 5.5Rank 1, published Sep 22, 2026
Leaderboard
Each model's latest published score. Every score links to its source.
Record history
The best score ever published on Epoch Capabilities Index, and who held it. Each step is a new record.
| Date | Record holder | ECI | Gain | Note |
|---|---|---|---|---|
| Sep 22, 2026 | Claude Opus 5.5Current | 169 | +0 | |
| Sep 3, 2026 | GPT-6 Astra | 169 | +2 | |
| Sep 1, 2026 | Claude Fable 5.1 | 166 | +3 | |
| Jul 24, 2026 | Claude Opus 5 | 164 | +1 | |
| Jun 9, 2026 | Claude Fable 5 | 163 | +1 | |
| Apr 23, 2026 | GPT-5.5 Pro | 163 | +3 | |
| Mar 5, 2026 | GPT-5.4 Pro | 160 | +9 | |
| Nov 24, 2025 | Claude Opus 4.5 | 150 | +0 | |
| Aug 7, 2025 | GPT-5 | 150 | +3 | |
| Apr 16, 2025 | o3 | 147 | +6 | |
| Feb 24, 2025 | Claude 3.7 Sonnet | 141 | +8 | |
| Oct 22, 2024 | Claude 3.5 Sonnet | 133 | First |
Method
Epoch AI's combined score across many benchmarks (CC BY 4.0). Higher is better. Board source: epoch.ai.
We collect the scores the board and the labs publish and run none ourselves. Ranks use each model's latest reading. 41 readings stored for this board, the newest from Oct 15, 2026. The record history includes older models that no longer have a page here.