Claude Fable 5.1
Anthropic's most capable generally available model, sharing weights with the gated Claude Mythos 5.1, with unchanged list prices, cache reads cut 75%, and a nine-benchmark launch table against Fable 5, Opus 5, and GPT-5.6 Sol.
Claude Fable 5.1 is available on MiniRouter as . The model page has current pricing, provider routes and API setup.
About the model
- Context: 1M. 128K maximum output on the synchronous API
- Effort: low → max. Five levels; the API defaults to high
- Cache read: $0.25 / 1M. Down from $1.00 on Fable 5; batch API is 50% off
- Knowledge cutoff: June 2026. Both reliable and training cutoffs per the model docs
Publisher pricing
Pricing below comes from the linked publisher sources and does not represent a MiniRouter route or price.
| Phase | Input / 1M | Output / 1M | Blended / 1M | Effective | Source |
|---|---|---|---|---|---|
| List | $10.00 | $50.00 | $20.00 | Sep 1, 2026 – open-ended | Anthropic ↗ |
Publisher-reported benchmarks
Results from the publisher’s announcement, grouped by unit.
| Benchmark | Reported result | Reported by | As of | Source |
|---|---|---|---|---|
| Terminal-Bench-Science 0.1 | 52.6% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| Terminal-Bench 4.0 | 55.8% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| CursorBench 3.2.0 | 73.4% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| AutomationBench | 31.4% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| OSWorld 2.0 · partial | 77.9% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| OSWorld 2.0 · strict | 41.7% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| Humanity's Last Exam · no tools | 60.9% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| Humanity's Last Exam · with tools | 65.0% | Anthropic | Sep 1, 2026 | Announcement ↗ |
| Benchmark | Reported result | Reported by | As of | Source |
|---|---|---|---|---|
| GDPval-AA v2 | 1,853 | Anthropic | Sep 1, 2026 | Announcement ↗ |
Anthropic says Fable 5.1 and Mythos 5.1 share the same underlying model and pricing; Mythos 5.1 is limited to approved organizations with fewer safeguards.
Forced tool use returns an error, other models cannot read Fable 5.1 thinking blocks, and editing earlier turns invalidates thinking; see Anthropic's migration guide.
Anthropic ran the launch table with production safeguards on; tasks they intervened in scored zero. MiniRouter has not reproduced the figures.
Independent measurements
Artificial Analysis evaluations of the first-party API.
Claude Fable 5.1 (max with fallback) ranks #1 of 462 model families on their Intelligence Index. Their headline uses the highest-scoring effort setting; every listed setting is below.
- Intelligence Index
- 53.4
- Composite of their evaluations
- Coding Index
- 81.6
- Coding evaluations only
- Blended price
- $20
- USD per 1M tokens, 3:1 input to output, first-party list
- Output speed
- 72
- Median tokens per second
- First answer token
- 132s
- Median seconds, including reasoning
| Setting | Intelligence Index | Coding Index | Blended price | Output speed | First answer token |
|---|---|---|---|---|---|
| Claude Fable 5.1 (max with fallback) ↗ | 53.4 | 81.6 | $20 | 72 | 132s |
| Claude Fable 5.1 (xhigh with fallback) ↗ | 53.2 | 80.7 | $20 | 61 | 34s |
| Claude Fable 5.1 (high with fallback) ↗ | 51.2 | 79.1 | $20 | 55 | 7.2s |
| Claude Fable 5.1 (medium with fallback) ↗ | 48.9 | 77.1 | $20 | 51 | 5.5s |
| Claude Fable 5.1 (low with fallback) ↗ | 46.8 | 75.2 | $20 | 51 | 4.5s |
Source: Artificial Analysis ↗, read Sep 21, 2026. Measured on the model's first-party API, not a MiniRouter route.
Keep exploring
Compare published results in the model rankings and coding benchmarks, or read more model releases.
For MiniRouter product updates, visit the changelog.
Sources
- Read at Anthropic ↗
Anthropic announcement
Published Sep 1, 2026
- Read at Anthropic ↗
Anthropic model docs
Published Sep 1, 2026
- Read at Artificial Analysis ↗
Artificial Analysis model page
Published Sep 21, 2026
Editorial reference revised 2026-10-17. Catalog status comes from the generated routing snapshot.