Claude Fable 5.1
claude-fable-5-1
These are Mengbi Router customer prices in USD per 1M tokens. Provider: Anthropic; Context: 1M; Input price: $4.29; Output price: $21.43.
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Model specs
- Provider
- Anthropic
- Context
- 1M
- Max output
- 64K
- Released
- Sep 2026
- Input modalities
- Text, Image, PDF
- Output modalities
- Text
- Tool calling
- Supported
- Structured output
- Supported
- Currency
- USD
- Model ID
- claude-fable-5-1
Model pricing and access details
USD / 1M tokens| Model | Official | Mengbi | Discount |
|---|---|---|---|
| Input price | $10 | $4.29 | 57% OFF |
| Output price | $50 | $21.43 | 57% OFF |
| Cache read price | $0.25 | $0.107 | 57% OFF |
Estimated cost for common usage
Estimates based on current Mengbi Router prices, so you can plan real request costs.
| Token volume | Input | Output | Input + output total |
|---|---|---|---|
| 10K tokens | $0.0429 | $0.214 | $0.257 |
| 100K tokens | $0.429 | $2.14 | $2.57 |
| 1M tokens | $4.29 | $21.43 | $25.71 |
| 10M tokens | $42.86 | $214.29 | $257.14 |
Estimates use the current prices above and exclude cache-hit discounts. Your invoice is metered by the actual token usage of each request.
API protocol compatibility
Keep your SDK. Change one line.
Use the protocol your stack already speaks.
const client = new OpenAI({
apiKey: process.env.MENGBI_ROUTER_KEY,
baseURL: process.env.MENGBI_ROUTER_BASE_URL,
})
const response = await client.chat.completions.create({
model: 'claude-fable-5-1',
messages,
})Frequently asked questions
Common questions about the Claude Fable 5.1 API: pricing, capabilities, and integration.
How much does the Claude Fable 5.1 API cost?
Through Mengbi Router, Claude Fable 5.1 costs $4.29 per 1M input tokens and $21.43 per 1M output tokens. Cached input is billed at $0.107 per 1M tokens.
What is the context window of Claude Fable 5.1?
Claude Fable 5.1 supports a 1M-token context window. A single request can generate up to about 64K output tokens.
Does Claude Fable 5.1 support tool calling and structured output?
Yes. Claude Fable 5.1 supports the tools parameter in chat.completions for function calling. It also supports response_format with a JSON Schema for structured output.
What input and output formats does Claude Fable 5.1 support?
It accepts Text, Image, and PDF and returns Text.
How do I call Claude Fable 5.1 with the OpenAI SDK?
Keep your OpenAI SDK, point the base URL at Mengbi Router, use your Mengbi API key, and set model to claude-fable-5-1 in the request.
Which company provides Claude Fable 5.1?
Claude Fable 5.1 is provided by Anthropic and available through Mengbi Router with one API key and pay-as-you-go billing. The model was first released in Sep 2026.