Model
Claude Fable 5.1 evaluated on the hub's only benchmark
Released on 1 September 2026, Claude Fable 5.1 (Anthropic) joins the hub's rankings: its place on the Business Index, its strongest and weakest business functions, its cost and its hallucination rate.
Report written by the hub from the published rankings: every sentence is computed, none is an opinion.
- 21st of 27 on the Business Index, at 98.5% (95% margin of error: ± 1.7 points).
- 0.8 index points below Claude Sonnet 5, its predecessor at Anthropic, released on 30 June 2026. The gap is smaller than the margin of error: the two models cannot be told apart.
- Mean cost per test: $0.072, the 26th cheapest of the 27 models with a known price.
- Mean hallucination rate: 0.0%, the share of items missing from the source for which it invented a value.
- It took the hub's only published benchmark.
Scores by business function
| Business function | Score |
|---|---|
| Finance | Not tested |
| Accounting | 98.5% |
| Human resources | Not tested |
| Legal | Not tested |
| Sales | Not tested |
| Marketing | Not tested |
| Customer service | Not tested |
| Procurement & logistics | Not tested |
| IT | Not tested |
| Management | Not tested |
| Business Index | 98.5% |