Anthropic
LLM
Big
Closed weights
Claude Fable 5.1
72 days since Anthropic announced it ·
Claude Fable 5.1 is a closed-weights LLM from Anthropic, announced 1 Sep 2026. It costs $10 per 1M input tokens and $50 per 1M output tokens. Its context window is 1M tokens.
- Input
- $10
- per 1M tokens
- Cache write
- $12.50
- per 1M tokens
- Cache read
- $0.25
- per 1M tokens
- Output
- $50
- per 1M tokens
- Context window
- 1M
- tokens
- Parameters
- —
- not disclosed
- Announcement
- anthropic.com/claude-fable-and-mythos-5-1
- Docs
- platform.claude.com/docs/en/models/fable-5-1/overview
Our coverage
We haven’t written about Claude Fable 5.1 yet.
Anthropic · Big · Fable
closed weights- Claude Fable 5.2 +69d
- Claude Fable 5.1 +84d
- Claude Fable 5
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