Anthropic
Anthropic's proprietary safety-constrained model for demanding reasoning, coding, and long-horizon agentic work. It is closed-weight software and cannot run locally as an open model.
58.3
Quality Score
1315
Arena ELO
Undisclosed
Parameters
1M
Context
Use this section to answer one simple question first: how much outside evidence do we have that this model performs well? Structured benchmark scores appear first, then official provider evidence, then live arena signal.
This model has normalized benchmark rows, so scores here are directly comparable across benchmark sources.
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14.9K
Downloads
0
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Jun 2026
Released
These are recent benchmark or leaderboard claims from official provider sources. They are useful for freshness and context, but they are not treated the same as normalized independent benchmark rows.
Claude Fable 5 and Claude Mythos 5
It is state-of-the-art on nearly all tested benchmarks of AI capability, showing exceptional performance in software engineering, knowledge work, vision, scientific research, and many other areas. Fable 5 is also more token-efficient than past Claude models: on Cognition’s FrontierCode evaluation, which tests whether models can pass difficult coding tasks while meeting the standards of high-quality production codebases, Fable 5 scores highest among frontier models, even at me
View sourceClaude Fable
Claude Fable \ Anthropic Skip to main content Skip to footer Research Policy Commitments Learn News Try Claude Claude Claude Fable 5 Next generation of intelligence for the hardest knowledge work and coding problems. It brings 5th-generation intelligence to your most ambitious coding and professional work. Read more Availability and pricing For individuals and organizations taking on their hardest knowledge and coding work, Claude Fable 5 is available to Pro, Max, Team, and E
View source1315
ELO Score
1306 - 1324
95% Confidence
+/-9 points
8.3K
Battles
Aug 14, 2026
Last Updated