Claude Fable 5.1
Anthropic · Claude model for demanding reasoning and long-horizon agentic work
Key facts
- Provider
- Anthropic
- Context window
- 1M tokens
- Max output
- 128K tokens
- Input price
- $10 / M tok
- Output price
- $50 / M tok
- Knowledge cutoff
- Jun 2026
- Released
- Sep 1, 2026
- License
- —
Capabilities
ReasoningTool callingStructured outputFile attachmentsTemperature controlOpen weights
Reasoning options
- effort low · medium · high · xhigh · max
Pricing
USD per million tokens, list API rates.
- Input
- $10
- Output
- $50
- Cache read
- $0.25
- Cache write
- $12.5
Modalities
- Input
- Text, Image, Pdf
- Output
- Text