Claude Fable 5Legacy
- Context window
- 1Mtokens
- Max output
- 128Ktokens
- Input pricing
- $10/ MTok
- Output pricing
- $50/ MTok
Fable vs. Mythos
Claude Mythos 5 is offered separately, by invitation only, for defensive cybersecurity workflows as part of Project Glasswing. It shares Claude Fable 5's specifications and pricing; Claude Fable 5 includes safety classifiers that can decline requests, and Claude Mythos 5 does not. For access, contact your Anthropic, AWS, or Google Cloud account team.
How it compares to the current lineup
| Model | Context | Max output | Price / MTok | Thinking | Default effort | Knowledge cutoff |
|---|---|---|---|---|---|---|
| Claude Fable 5.1 | 1M | 128K | $10 / $50 | Adaptive (always on) | high | Jun 2026 |
| Claude Fable 5This modelLegacy | 1M | 128K | $10 / $50 | Adaptive (always on) | high | Jan 2026 |
| Claude Opus 5 | 1M | 128K | $5 / $25 | Adaptive | high | May 2026 |
| Claude Sonnet 5 | 1M | 128K | $2 / $10 | Adaptive | high | Jan 2026 |
| Claude Haiku 4.5 | 200K | 64K | $1 / $5 | Extended | — | Feb 2025 |
Specifications
Model IDs
- Claude API
Pricing
- Input
- $10 / MTok
- Output
- $50 / MTok
- 5m cache write
- $12.50 / MTok
- 1h cache write
- $20 / MTok
- Cache read
- $1 / MTok
- Batch API
- 50% discount on input and output
- Full price list
- Pricing
Capabilities
- Context window
- 1M tokens
- Max output
- 128K tokens
- Thinking
- Adaptive (always on)
- Default effort
high- Input → output
- Text and images → text
- Reliable knowledge cutoff
- Jan 2026
- Training data cutoff
- Jan 2026
Availability
- Status
- Active (legacy)
- Released
- June 9, 2026
- Retirement
- Not sooner than June 9, 2027
- Platforms
- Claude APIAmazon BedrockGoogle CloudMicrosoft FoundryClaude Platform on AWS
Resources
What changes when moving from Claude Fable 5 to Claude Fable 5.1.
The current Fable model: overview, specs, and resources.
Capabilities, API changes, and availability for Claude Fable 5.
Model-specific prompting guidance for long-horizon and agentic work.
Handle classifier refusals and retry on another Claude model with the fallbacks parameter.
Reference
The system prompt Claude Fable 5 uses on claude.ai and the Claude apps.
Safety evaluations and deployment decisions for Claude Fable 5 and Claude Mythos 5.
Full price list, including batch discounts and prompt caching rates.
How model IDs, aliases, and pinned snapshots work.
Lifecycle status and retirement commitments for every Claude model.
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