ApX logoApX logo

Claude Fable 5.1

Parameters

Undisclosed

Context Length

1M

Modality

Multimodal

Architecture

Undisclosed

License

Proprietary

Release Date

1 Sept 2026

Knowledge Cutoff

Jun 2026

API Pricing (per 1M)

Input: $10.00 · Output: $50.00

Evaluation Benchmarks

Rank

#1

BenchmarkScoreRank
max

0.83

🥇

1

max

0.86

🥇

1

max

0.92

🥇

1

Agentic Coding

LiveBench Agentic
max

0.66

🥇

1

max

0.97

🥇

1

LiveBench Average

LiveBench Average
max

0.83

🥇

1

Web Development

WebDev Arena
max

1763

🥇

1

Intelligence Index

Artificial Analysis
max

0.57

high

0.52

medium

0.50

low

0.48

🥇

1

6

10

16

max

0.82

high

0.79

medium

0.77

low

0.75

🥇

1

🥈

2

6

17

Agentic Index

Artificial Analysis
max

0.58

high

0.54

medium

0.51

low

0.48

🥇

1

7

14

19

max

0.80

🥉

3

General Text

Text Arena
max

1504

🥉

3

Rankings

Overall Rank

#1 🥇

Coding Rank

#1 🥇

About Claude Fable 5.1

Claude Fable 5.1 is an advanced multimodal reasoning and agentic model by Anthropic, offering improvements across coding, long-running agent workflows, and knowledge tasks. It features a 1M token context window tailored for extensive codebase refactoring and visual analysis.

Technical Specifications

Architecture specifications are undisclosed for proprietary models.

About Claude Fable 5

Anthropic's Claude Fable 5 generation, released June 9, 2026, shares a unified frontier architecture with Mythos 5, incorporating advanced safety classifiers for cybersecurity, biology, and chemistry, with fallback routing to Claude Opus 4.8.


Other Claude Fable 5 Models
Claude Fable 5.1: Model Specifications and Details