Claude Fable 5.1: Release Intelligence, Performance & Price
Available providers
Model summary
Verbosity
The Claude Fable 5.1 release offers 5 models, each with different intelligence, performance, and pricing characteristics. Below is a comparison of the key metrics across the 5 models.
- For intelligence, the top model of Claude Fable 5.1 is Claude Fable 5.1 (Xhigh, Default Fallback) at 50.
- For output speed, the fastest model is Claude Fable 5.1 (Max, Default Fallback) at 69 t/s.
- For latency, Claude Fable 5.1 (Low, Default Fallback) at 2.27s offers the lowest time to first answer token.
- For pricing, Claude Fable 5.1 (Low, Default Fallback) at $4.47 offers the lowest cost per task. Prices vary up to 2.9x across models.
| Reasoning | Yes This page shows the reasoning version of this model. A non-reasoning variant may also exist. |
|---|---|
| Input modality | Supports: text and image |
| Output modality | Supports: text |
| Context window | 1M ~1500 A4 pages of size 12 Arial font |
Metrics are compared against models of the same class:
- Non-reasoning models → compared only with other non-reasoning models
- Reasoning models → compared across both reasoning and non-reasoning
- Open weights models → compared only with other open weights models of the same size class:
- Tiny: ≤4B parameters
- Small: 4B–40B parameters
- Medium: 40B–150B parameters
- Large: >150B parameters
- Proprietary models → compared across proprietary and open weights models of the same price range, using a blended 3:1 input/output price ratio:
- <$0.15 per 1M tokens
- $0.15–$1 per 1M tokens
- >$1 per 1M tokens
Intelligence
Artificial Analysis Intelligence Index
Intelligence Index vs. Cost per Task
Cost
Cost per Intelligence Index Task
Speed & Latency
Output Speed
Capability Scores
Capability Indexes
Incorporates 5 evaluations: AA-Briefcase v1.1, AA-Omniscience v1.1, HLE-Diamond, AutomationBench-AA, GDP.pdf · Higher is better
Incorporates 4 evaluations: AutomationBench-AA, AA-Briefcase v1.1, AA-Omniscience v1.1, GDP.pdf · Higher is better
Incorporates 5 evaluations: AA-Omniscience v1.1, AA-Briefcase v1.1, HLE-Diamond, GDP.pdf, AutomationBench-AA · Higher is better
Incorporates 5 evaluations: AA-Omniscience v1.1, AA-Briefcase v1.1, MLCR-AA, AutomationBench-AA, HLE-Diamond · Higher is better
Incorporates 7 evaluations: AA-Omniscience v1.1, CritPt v2 (Hard Subset), Terminal-Bench-Science 0.1, HLE-Diamond, Terminal-Bench 4.0, FrontierCode 2.0, AA-Briefcase v1.1 · Higher is better
Incorporates 4 evaluations: AA-Briefcase v1.1, AA-Omniscience v1.1, HLE-Diamond, GDP.pdf · Higher is better
Evaluations
Agentic knowledge work, Elo
Knowledge
1 - hallucination rate
Agentic SaaS workflows
Agentic scientific research workflows in a terminal
Agentic software engineering in open-source repositories
Reasoning & knowledge
Professional document reasoning, All-pass
Agentic coding & terminal use
Physics reasoning
Quantitative analysis on spreadsheets & documents
Legal agentic work, Hallucination-Gated All-Pass Rate
Agentic real-world work tasks, Elo
Agentic interactive 3D experiences, Elo
Product and brand videos designed in code, Elo
Kubernetes incident root-cause analysis
Medical long context reasoning
Rich, varied, well-crafted language
Well-structured, scannable, answer-first
Truthful, acknowledges uncertainty, non-sycophantic
Use of filler and generic language
AA-PersonalityBench
Personality Indexes
More from Anthropic
Further details
Weights | Provider Benchmarks | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Claude Fable 5.1 (Xhigh, Default Fallback) |  Anthropic | 50 | - | 1M | $7.2 | 62 | Not available | | |
| Claude Fable 5.1 (Max, Default Fallback) | Anthropic | 49 | - | 1M | $7.2 | 69 | Not available | | |
| Claude Fable 5.1 (High, Default Fallback) | Anthropic | 47 | - | 1M | $7.2 | 57 | Not available | | |
| Claude Fable 5.1 (Medium, Default Fallback) | Anthropic | 43 | - | 1M | $7.2 | 55 | Not available | | |
| Claude Fable 5.1 (Low, Default Fallback) | Anthropic | 38 | - | 1M | $7.2 | 55 | Not available | |