Source: Epoch AI (CC BY 4.0). ECI is Epoch's item-response model over many benchmarks; each model page shows its 90% confidence interval.
Only models with both an ECI score and an OpenRouter price. Normalisation: 75% input + 25% output price. Click a point to open the model.
| # | Model | ECI ↓ | Context | In $/M | Weights | Released |
|---|---|---|---|---|---|---|
| 1 | Claude Fable 5.1 Anthropic· reasoning | 165.0 | 1M | $10.0 | Closed | 1 Sep 2026 |
| 2 | Claude Opus 5.5 Anthropic· reasoning | — | 1M | $4.00 | ? | 22 Sep 2026 |
| 3 | Claude Opus 5.5 (batch) Anthropic· reasoning | — | 1M | $2.00 | ? | 22 Sep 2026 |
| 4 | Claude Fable 5.1 (batch) Anthropic· reasoning | — | 1M | $5.00 | ? | 1 Sep 2026 |
| 5 | Claude Sonnet 5.5 Anthropic· reasoning | — | 1M | $2.00 | ? | 28 Sep 2026 |
| 6 | Claude Sonnet 5.5 (batch) Anthropic· reasoning | — | 1M | $1.00 | ? | 28 Sep 2026 |
| 7 | Claude Fable 5.1 (xhigh) | — | — | — | Closed | 1 Sep 2026 |
| 8 | Claude Fable 5.1 (medium) | — | — | — | Closed | 1 Sep 2026 |
| 9 | Claude Fable 5.1 (low) | — | — | — | Closed | 1 Sep 2026 |
| 10 | Claude Fable 5.1 (unknown) | — | — | — | Closed | 1 Sep 2026 |