# Did Claude change today?

**As of 2026-09-04, no tracked Claude model changed its pass count versus the previous run. 5 models measured on the same 12-task battery.**

## Last 5 readings

| Run | haiku-4-5 | sonnet-5 | opus-5 | fable-5 | fable-5-1 |
|---|---:|---:|---:|---:|---:|
| 2026-09-04 | 11/12 | 12/12 | 12/12 | 12/12 | 12/12 |
| 2026-09-03 | 11/12 | 12/12 | 12/12 | 12/12 | 12/12 |
| 2026-09-02 | 11/12 | 11/12 | 10/12 | - | - |
| 2026-09-01 | 11/12 | 12/12 | 11/12 | - | - |
| 2026-08-31 | 11/12 | 12/12 | 12/12 | - | - |

How this is measured: the same versioned battery, every tracked model, every morning, frozen request shape, deterministic scoring. https://winthropic.com/methodology.md

Cite: Winthropic Index, "Did Claude change today?", reading of 2026-09-04, https://winthropic.com/did-claude-change-today

Winthropic is an independent measurement project and is not affiliated with, endorsed by, or connected to Anthropic. Paying for output you are not getting? https://winthropic.com/audit.md prices your actual spend from a usage export; the summary is free.