Capability
82.7/100
field median 58.2
#1 of 229 ranked models
Claude Fable 5.1
CurrentReleased Sep 1, 2026ProprietaryReasoning1M contextClaude Fable 5.1 and Claude Mythos 5.1 system card
Released Sep 1, 2026 — see all recent releases
Decision reading
Claude Fable 5.1 scores 82.7 out of 100 and ranks #1 of 229. This profile shows 18 source-displayable benchmark rows; its strongest eligible category is Agentic at #2. API pricing is $10 input and $50 output per million tokens, with cached input at $0.25.
Data as of September 1, 2026 · How the score is built
Strongest published evidence
Agentic ranks #2. Particularly useful for coding agents, browser research, and computer-use workflows.
Validate before choosing
18 published rows leave some tracked benchmark slots empty. Knowledge is its lowest eligible category at #2.
Decision snapshot
Each value carries a field reference instead of floating alone. Markers compare this model with the current ranked and priced catalog; they are not absolute quality thresholds.
Price
$10input / $50 output
input median $1
cached $0.25 · blended $30
Speed
66tok/s
field median 89 tok/s
First token 285.33 s
Context
1Mtokens
field median 256,000
Maximum output length is tracked separately
Capability shape
Each axis shows percentile within that category’s eligible cohort. The comparison outline is the median of the six nearest public-score peers; a collapsed vertex means the category is not rank-eligible.
Claude Fable 5.1 category percentile values
- Agentic99th percentile
- Coding99th percentile
- ReasoningNot eligible
- Knowledge98th percentile
- MathNot eligible
- MultilingualNot eligible
- MultimodalNot eligible
- Instruction followingNot eligible
The dashed outline is median of 6 nearest peers.
Eligible category ranks
- Agentic#2/142
- Coding#2/147
- ReasoningNot ranked
- Knowledge#2/56
- MathNot ranked
- MultilingualNot ranked
- MultimodalNot ranked
- Inst. FollowingNot ranked
Top decileTop quartileMid-fieldNot eligible
What it costs to get this score
Published API price against the public score. The x-axis uses a log scale; the dashed path marks models that are not beaten by a cheaper, higher-scoring option. Price uses average of published input and output rates.
The chart opens on the current model. Scroll horizontally to inspect the full price axis.
Current modelClaude Fable 5.1 · 82.7 score · $30 blended per million tokens
Horizontal: blended price per million tokens, log scale · Vertical: public score
How much of this is verified
Coverage is split by category so a strong number never hides a thin evidence base. Verified means the row is tied to a published source; provisional rows remain visible but separate.
- Agentic8/8 verified
- Coding6/6 verified
- Reasoning2/2 verified
- Knowledge2/2 verified
- MathNot measured
- MultilingualNot measured
- MultimodalNot measured
- Inst. FollowingNot measured
Verified sourceProvisionalNot measured
Spec sheet
Each documented value carries its source. Missing fields stay visible as not sourced or not published, rather than disappearing from the page.
- API model ID
- claude-fable-5-1Anthropic Fable 5.1 and Mythos 5.1 launch
- Context window
- 1MClaude Fable 5.1 and Claude Mythos 5.1 system card
- Maximum output
- Not sourced yet
- Knowledge cutoff
- Not sourced yet
- Input modalities
- Not sourced yetClaude Fable 5.1 and Claude Mythos 5.1 system card
- Output modalities
- Not sourced yetClaude Fable 5.1 and Claude Mythos 5.1 system card
- Parameters
- Not disclosed by the provider
- Availability
- Claude API · Claude products · AWS · Google Cloud · Microsoft AzureAnthropic Fable 5.1 and Mythos 5.1 launch
- Cloud regions
- Not tracked yet
- Lifecycle
- activeAnthropic Fable 5.1 and Mythos 5.1 launch
- API capabilities
- Tool calling, structured outputs, and batch support are not tracked yet
- Prompt caching
- Published at $0.25 per million cached input tokensAnthropic Fable 5.1 launch
- Self-host
- Weights are not published
- Rate limits
- Not tracked yet
Category score record
Scores and ranks appear only where published evidence can be displayed. The table keeps the score, weight, cohort, and evidence state together.
| Category | Score | Rank | Percentile | Weight | Benchmarks | Evidence |
|---|---|---|---|---|---|---|
| AgenticRank #2 of 142Percentile 99thWeight 22%8 benchmarksVerified | 76.4 | #2 of 142 | 99th | 22% | 8 benchmarks | Verified |
| CodingRank #2 of 147Percentile 99thWeight 20%6 benchmarksVerified | 79.4 | #2 of 147 | 99th | 20% | 6 benchmarks | Verified |
| ReasoningRank Not rankedWeight 17%2 benchmarksVerified | 83.1 | Not ranked | Not available | 17% | 2 benchmarks | Verified |
| KnowledgeRank #2 of 56Percentile 98thWeight 12%2 benchmarksVerified | 97.0 | #2 of 56 | 98th | 12% | 2 benchmarks | Verified |
| MathWeight 5%0 benchmarksNot measured | Not measured | Not ranked | Not available | 5% | 0 benchmarks | Not measured |
| MultilingualWeight 7%0 benchmarksNot measured | Not measured | Not ranked | Not available | 7% | 0 benchmarks | Not measured |
| MultimodalWeight 12%0 benchmarksNot measured | Not measured | Not ranked | Not available | 12% | 0 benchmarks | Not measured |
| Inst. FollowingWeight 5%0 benchmarksNot measured | Not measured | Not ranked | Not available | 5% | 0 benchmarks | Not measured |
Benchmark ledger
Coding opens by default. The marker compares each value with the best source-verified result in the catalog; provisional leaders do not set the reference. Expand the remaining categories for every published row.
Coding6 rows
| Benchmark | Score | Versus best verified row | Gap | Weight | Evidence |
|---|---|---|---|---|---|
| SWE-bench Pro | Score81.2% | Versus best verified row Best verified: Claude Fable 5.1 · 81.2% | GapBest verified | WeightWeighted 10% | |
| SWE Multilingual | Score89.1% | Versus best verified row Best verified: Claude Opus 5 · 89.5% | Gap0.4 behind | WeightDisplay only | |
| SWE MultimodalSWE-bench Multimodal | Score54.7% | Versus best verified row Best verified: Claude Opus 5 · 59.4% | Gap4.7 behind | WeightDisplay only | |
| deepSwe | Score67.4% | Versus best verified row Best verified: GPT-5.6 Sol · 72.7% | Gap5.3 behind | WeightDisplay only | |
| ProgramBenchProgramBench: Can Language Models Rebuild Programs From Scratch? | Score87.6% | Versus best verified row Best verified: Claude Opus 5 · 93.0% | Gap5.4 behind | WeightDisplay only | |
| cursorBench32 | Score73.4% | Versus best verified row Best verified: Claude Fable 5.1 · 73.4% | GapBest verified | WeightDisplay only | Benchmark exact |
Agentic8 rows
| Benchmark | Score | Versus best verified row | Gap | Weight | Evidence |
|---|---|---|---|---|---|
| Terminal-Bench 4.0 | Score55.80% | Versus best verified row Best verified: Claude Mythos 5.1 · 60.90% | Gap5.1 behind | WeightDisplay only | |
| Terminal-Bench-Science 0.1 | Score52.6% | Versus best verified row Best verified: Claude Fable 5.1 · 52.6% | GapBest verified | WeightDisplay only | |
| OSWorld 2.0 | Score41.7% | Versus best verified row Best verified: Claude Opus 5 · 70.6% | Gap28.9 behind | WeightDisplay only | |
| AutomationBench | Score31.4% | Versus best verified row Best verified: GLM-5.3-Flash · 48.8% | Gap17.4 behind | WeightDisplay only | |
| Toolathlon-Verified | Score77.8% | Versus best verified row Best verified: Claude Opus 5 · 80.6% | Gap2.8 behind | WeightDisplay only | |
| Toolathlon Verified Pass@3 | Score81.5% | Versus best verified row Best verified: Claude Opus 5 · 87.0% | Gap5.5 behind | WeightDisplay only | |
| Toolathlon Verified Pass³Toolathlon Verified Pass cubed | Score73.1% | Versus best verified row Best verified: Claude Opus 5 · 73.1% | GapBest verified | WeightDisplay only | |
| Toolathlon Verified avg. turnsToolathlon Verified average assistant turns | Score23.7 turns | Versus best verified row Best verified: Claude Fable 5.1 · 23.7 turns | GapBest verified | WeightDisplay only |
Reasoning2 rows
| Benchmark | Score | Versus best verified row | Gap | Weight | Evidence |
|---|---|---|---|---|---|
| ARC-AGI-2Abstraction and Reasoning Corpus for AGI v2 | Score90% | Versus best verified row Best verified: GPT-5.6 Sol · 92.5% | Gap2.5 behind | WeightWeighted 31% | |
| ARC-AGI-1ARC-AGI-1 Semi-Private Evaluation | Score97.50% | Versus best verified row Best verified: Claude Opus 5 · 97.50% | GapBest verified | WeightDisplay only |
Knowledge2 rows
| Benchmark | Score | Versus best verified row | Gap | Weight | Evidence |
|---|---|---|---|---|---|
| HLEHumanity's Last Exam | Score65% | Versus best verified row Best verified: Claude Fable 5.1 · 65% | GapBest verified | WeightWeighted 45% | |
| HLE w/o toolsHumanity's Last Exam without tools | Score60.9% | Versus best verified row Best verified: Claude Fable 5.1 · 60.9% | GapBest verified | WeightDisplay only |
Lineage
The sequence follows explicit supersedes links. Scores and prices remain blank when the corresponding public row or first-party rate is unavailable.
Jun 9, 2026
Claude Fable 5Score 82.5 · $10 / $50
Sep 1, 2026 · you are here
Claude Fable 5.1Score 82.7 · $10 / $50
Base entry
How to read this profile
The visual layer above carries the decisions. These notes preserve the model, ranking, coverage, and family context behind the numbers.
Claude Fable 5.1 ranks #1 of 229 on the public leaderboard with a score of 82.74/100. It does not yet have enough sourced coverage for a verified position.
Claude Fable 5.1 is a proprietary model with a 1M context window. It uses an explicit reasoning mode, which can improve complex problem solving while adding latency and token use.
Generally available on the Claude API as `claude-fable-5-1` and across Anthropic, Amazon Web Services, Google Cloud, and Microsoft Azure. Fable 5.1 allows defensive vulnerability discovery, while exploit generation and some dual-use cyber work still route to Opus models. Eligible enterprise customers can use zero data retention until Enterprise Frontier Safeguards rolls out in phases beginning later in fall 2026.
Official exact-value snapshot from Anthropic's September 2026 Claude Fable 5.1 and Claude Mythos 5.1 launch page and system card, supplemented by Cursor's live CursorBench 3.2 table. We store only exact protocol matches, including the highest published effort where several settings are shown. OSWorld 2.0 uses the strict pass rate and records the paired partial score in provenance. Independent LiveBench and Vals evidence now clears the provisional external-consensus gate; the verified rank remains withheld until more weighted benchmark categories clear their coverage thresholds.
Claude Fable 5.1 sits in the Claude Fable family with Claude Fable 5. Its explicit predecessor is Claude Fable 5. 18 of 408 tracked benchmark slots currently have displayable evidence. Missing categories stay blank.
Its strongest eligible category is Agentic at #2, while its lowest eligible position is Knowledge at #2. particularly useful for coding agents, browser research, and computer-use workflows.
Radar
Full release historyClaude Fable 5.1 release history
Claude Fable 5.1 and Claude Mythos 5.1 released
Anthropic · Model release
Source confirmed
Radar confirmed these at the source. Already tracking Claude Fable 5.1? See the free Radar Brief for what changes next.
Frequently asked questions
How does Claude Fable 5.1 perform overall in AI benchmarks?
Claude Fable 5.1 ranks #1 out of 229 models on the public BenchAlign leaderboard, with a score of 82.74/100. Its evidence status is Estimated, and this profile shows 18 source-displayable benchmark rows. The label describes evidence depth, not a provider quality claim; inspect category rows before choosing a workload.
Is Claude Fable 5.1 good for knowledge and understanding?
Claude Fable 5.1 ranks #2 out of 56 eligible models for knowledge and understanding, with a public category score of 97/100. That places it in the current top ten for this category. Check the underlying rows before treating the aggregate as a workload guarantee.
Is Claude Fable 5.1 good for coding and programming?
Claude Fable 5.1 ranks #2 out of 147 eligible models for coding and programming, with a public category score of 79.4/100. That places it in the current top ten for this category. Check the underlying rows before treating the aggregate as a workload guarantee.
Is Claude Fable 5.1 good for reasoning and logic?
Claude Fable 5.1 has source-displayable benchmark coverage for reasoning and logic, but the public category table does not assign it a rank there. The individual rows remain available for inspection. A missing category position means the evidence threshold was not met; it does not convert the model's unmeasured work into a zero.
Is Claude Fable 5.1 good for agentic tool use and computer tasks?
Claude Fable 5.1 ranks #2 out of 142 eligible models for agentic tool use and computer tasks, with a public category score of 76.4/100. That places it in the current top ten for this category. Check the underlying rows before treating the aggregate as a workload guarantee.
Which sibling models are related to Claude Fable 5.1?
Claude Fable 5.1 belongs to the Claude Fable family. Related tracked variants include Claude Fable 5. A sibling link indicates shared lineage or a documented configuration relationship; it does not mean the variants have identical pricing, context limits, benchmark evidence, or deployment behavior. Compare before switching.
Does Claude Fable 5.1 have full benchmark coverage on BenchLM?
No. Claude Fable 5.1 currently has 35 source-displayable rows across 408 tracked benchmark slots. The profile exposes published, non-generated evidence and leaves missing categories blank until an exact evaluation is available. Coverage describes how much was measured; it is not a penalty added to an individual benchmark result.
What is the context window size of Claude Fable 5.1?
Claude Fable 5.1 has a documented context window of 1M. That figure is the maximum combined prompt and retained-conversation space reported for this exact model; it is not the maximum output length. The profile keeps output limits separate because providers often publish those limits independently.
Compare Claude Fable 5.1 with every tracked model405 comparisons
Last updated September 1, 2026. Runtime fields remain blank until a sourced snapshot exists.
Watch Claude Fable 5.1 in the weekly brief
Get one weekly email when material rank, price, availability, or benchmark evidence changes are worth revisiting.
Read a sample issueJoin 2,000+ readers.