Anthropic·anthropic/claude-fable-5.1
Claude Fable 5.1 is ModelCap current-board rank #2 with Index 84.1 (Measured), from the ModelCap Index as of 3 Sept 2026, 01:06 UTC.
Claude Fable 5.1 listed OpenRouter input price is $10.00 per 1M tokens and listed output price is $50.00 per 1M tokens, from OpenRouter listed prices as of 3 Sept 2026, 01:06 UTC.
Claude Fable 5.1 has a published context limit of 1M tokens in the ModelCap catalogue as of 3 Sept 2026, 01:06 UTC.
Claude Fable 5.1 has 4 published OpenRouter serving endpoints, from OpenRouter as of 3 Sept 2026, 01:06 UTC.
Claude Fable 5.1 weight access is api only, from ModelCap classification of published repository metadata as of 3 Sept 2026, 01:06 UTC.
Snapshot facts · download the public dataset · methodology
BES normalizes admitted public benchmark evidence for measured Index rows. Its legacy score and observables prior do not define the public language rank.
These adoption and deployment observations remain context only. They do not change this model's ModelCap Index score or rank.
The bounded 0–100 capability score blends each source’s competitive placement with its published achievement, then combines capability families. Evidence breadth adds a modest uncertainty adjustment; price and popularity are not part of benchmark-led rank.
Missing: artifactReproducibility.revision-sha, artifactReproducibility.architecture-and-model-type, artifactReproducibility.parameter-count, artifactReproducibility.serialized-weight-format, artifactReproducibility.base-lineage, accessLegalClarity.declared-license, accessLegalClarity.resolvable-license-terms, evaluationProvenance.evaluation-dataset-revisions.
A metadata completeness and deployability index—not a safety certification, quality grade, or production-readiness claim.
Market Gravity uses OpenRouter’s full-catalogue popularity order. Sparse Vercel top-ten observations appear only when published and do not affect the score.
This model is visible because it is available in the live catalogue, but it has no trustworthy community result yet. ModelCap does not infer a quality score from price, features, or market activity.
OpenRouter weekly popularity across the full model catalogue.
Independent providers versus the model's open or closed cohort, weighted by uptime.
Hugging Face 30-day downloads for open models; neutral for closed models.
Time since first public availability, on a six-month half-life.
Models within 3 places of #2 on the ModelCap Index.
Index score within 3 points of, or above, this model's, with a lower listed blended price (3:1 input:output).
The same publisher's other current models with a public Index position.
Claude Fable 5.1 holds ModelCap Index position #2 of 225 ranked language models as of 3 September 2026, with an Index score of 84.1 (interval 84.1–100.0); evidence: measured. The Index combines public benchmark boards with published uncertainty; the methodology page explains the weighting.
Claude Fable 5.1 is listed at $10.00 per 1M input tokens and $50.00 per 1M output tokens as of 3 September 2026 across 4 providers. Prices come from the OpenRouter catalogue and re-observe on every refresh.
Claude Fable 5.1 has a published context window of 1M tokens (1,000,000) and a maximum output of 128K tokens. Individual providers can serve less than the published maximum; the providers table lists each endpoint's own limit.
API only. No downloadable model weights are linked in the current source data; access is through a hosted API or product.
4 providers serve Claude Fable 5.1 through OpenRouter as of 3 September 2026: Google, Amazon Bedrock, Anthropic and Azure. Each provider's price, context limit, quantization and measured uptime are in the providers table above.
Claude Fable 5.1 has published results on 4 public boards tracked by ModelCap as of 3 September 2026: ARC-AGI-2 90.0% (#3 of 207), AA Intelligence Index 65.7 (#1 of 623), AA Terminal-Bench 2.1 91.4% (#1 of 226) and AA Humanity's Last Exam 59.1% (#1 of 591). Each board page ranks every tracked model on that benchmark; the ModelCap Index combines them with published uncertainty.
Claude Fable 5.1 ranks #2 (Index 84.1) and Claude Opus 5 ranks #3 (Index 83.6) on the ModelCap Index as of 3 September 2026. The head-to-head page lines up their benchmarks, listed prices, context windows and provider counts side by side.
Claude Fable 5.1 first appeared in the catalogue on 1 Sept 2026. It is the current version in its family. Rank and price movements since then are recorded on the site's changes feed.