MODEL PROOF
Claude Fable 5.1
BETTER VALUE OPTION
A stored alternative has an equal-or-higher measured score and an equal-or-lower price.
Claude Opus 5.5 · Δ score 1.1 points · 60% lower measured price · $8.00 / 1M tokens
- Independent LMArena score
- 1,510.6 ± 6.39 · 11,800 votes
- Context window
- 1M
- Maximum output
- 128K
- Input modalities
- text, image, file
- Output modalities
- text
- Published input price
- $10.00 / 1M tokens
- Published output price
- $50.00 / 1M tokens
- Pricing kind
- fixed
Inspect complete billing conditions and endpoint terms below.
Price from Anthropic: the cheapest offer that is serving, at standard delivery and at the maker’s precision or better, at its standard rate.
Every price dimension · USD per million tokens
| Input | $10.00/M |
|---|---|
| Output | $50.00/M |
| Cached input | $0.250/M |
| Cache write | $12.50/M |
| Cache write 1h | $20.00/M |
| Reasoning | Unknown/M |
| Web search | $0.01/call |
Who sells it
The same weights, different shops. Cheapest is not like-for-like when serving precision differs.
4 provider offers · rates, limits and conditions
Rates are USD per million tokens. Endpoint terms can differ even when the quoted price and precision match. A listed parameter is a provider declaration, not a task-success test.
| Seller | Input | Output | Precision | Uptime (1d) |
|---|---|---|---|---|
| Azureazure Endpoint terms
| $10.00 | $50.00 | undeclared | 99.25% |
| Anthropicanthropic Endpoint terms
| $10.00 | $50.00 | undeclared | 99.68% |
| Amazon Bedrockamazon-bedrock Endpoint terms
| $10.00 | $50.00 | undeclared | — |
| Googlegoogle-vertex/global Endpoint terms
| $10.00 | $50.00 | undeclared | 99.91% |
Independent scores
| LMArena Elo | 1510.6max |
|---|
LMArena Elo under CC BY 4.0. Absence of another board is not a score of zero.
Best rankings by task
- Full-stack apps #1 1325
- Web apps #1 1310
- Godot games #1 1327
- Python pptxslides #1 1328
- Game development #2 1394
- 3D #3 1401
- ASCII art #3 1333
- Mobile apps #3 1265
Per-task Elo and rank from Design Arena, via OpenRouter’s model feed. The rank is the feed’s, and it counts models OpenRouter does not list.
Capability
| Context window | 1M |
|---|---|
| Max output | 128K |
| Input modes | text, image, file |
| Tool use | yes |
| Reasoning | always on |
| Open weights | no |
Provenance
| Price source | openrouter.ai |
|---|---|
| Fetched | 2026-10-06 |
| Quality data | verified |
Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual...
Questions this page answers
What does Claude Fable 5.1 cost?
$10.00/M in, $50.00/M out in this catalogue, as of the fetch date on this page. That is the API row, not a subscription.
Does Claude Fable 5.1 have an independent quality score?
Claude Fable 5.1 has an LMArena score in this catalogue.
What beats Claude Fable 5.1?
Claude Opus 5.5 has an equal-or-higher measured score and an equal-or-lower price.
Does this page use Artificial Analysis scores for Claude Fable 5.1?
No. Artificial Analysis figures are not published here. Quality on this page is LMArena Elo where a score exists; otherwise the row is unrated.
MODEL MONUMENT
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The verdict as one SVG, for a README or a docs page. It states this model's dominance status at the balanced workload on the LMArena lens, with the date it was computed, and it is rebuilt with the catalogue — so it changes when the verdict changes, including to one you would rather it did not.
[](https://undominated.ai/models/anthropic__claude-fable-5.1/)<a href="https://undominated.ai/models/anthropic__claude-fable-5.1/"><img src="https://undominated.ai/badge/anthropic__claude-fable-5.1.svg" alt="Claude Fable 5.1 — Undominated.ai dominance verdict" height="36"></a>Direct file: https://undominated.ai/badge/anthropic__claude-fable-5.1.svg — a static SVG, written by scripts/build-badges.mjs on every build, so the copy you embed is never
older than the last deploy.
