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Next generation of intelligence for the hardest knowledge work and coding problems.
Next generation of intelligence for the hardest knowledge work and coding problems.
New Introducing Claude Fable 5.1 Sep 1, 2026 Our most capable model for coding and knowledge work, with research capabilities that offer an early glimpse of how AI will soon contribute to scientific progress. Read more -
For individuals and organizations taking on their hardest knowledge and coding work, Claude Fable 5.1 is available to Pro, Max, Team, and Enterprise users. For developers interested in building AI solutions that demand f
Claude Fable 5.1 includes robust safeguards for cybersecurity and biology. Many queries in these domains are automatically routed to less capable models if flagged by these safeguards. You won’t be charged Fable prices f
Using Fable requires 30-day data retention for safety monitoring by default. Enterprise customers eligible for Enterprise Frontier Safeguards can store data on their own cloud infrastructure and any human review is by de
Claude Fable 5.1 sets a new standard on coding, knowledge work, and long-running problem-solving tasks. Fable 5.1 was evaluated with its production safeguards enabled. On tasks where these safeguards intervened, Fable 5.
In internal benchmarks, Claude Fable 5.1 solves more of our coding problems than Fable 5 or Opus 5, and achieves state of the art on trading intuition. While prior models became hard to follow the longer they worked, Fab