Claude Fable 5

Best for

Coding, deep reasoning, and agent workflows

Superseded by

Claude Fable 5.1

• Context window

  1,000,000 tokens

  ≈ 750,000 words · about 3,000 pages

• Max output

  128,000 tokens

  ≈ 96,000 words in a single answer

• Knowledge cutoff

  January 2026

  its training cutoff

Modalities

• TextInput and output
• ImageInput only
• AudioNot supported
• VideoNot supported

Reasoning effort

Default: High.

• Low

• Medium

• High

• X-High

• Max

Features

• StreamingSupported
• Function callingSupported
• Structured outputsSupported
• Fine-tuningNot supported

Tools

• Web searchSupported
• Code interpreterSupported