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Anthropic

Claude Fable 5.1 on Anthropic

Claude Fable · Anthropic

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Last refreshed 2026-09-01. Next refresh: weekly.

Why use Claude Fable 5.1 on Anthropic?

Anthropic offers Claude Fable 5.1 with pay-as-you-go pricing at $10.00/1M input tokens. Anthropic is a safety-focused AI research company and creator of the Claude model family, offering API access through the Anthropic Console for text generation, analysis, and coding tasks.

Compare Claude Fable 5.1 across 4 providers to find the best fit for your use case
Input / 1M
$10.00
Output / 1M
$50.00
Cache
read $0.25 / 5m $12.50 / 1h $20.00
Batch
-50% · in $5.00 / out $25.00

Setup recipe

Python + curl
Install
pip install anthropic
Auth
export ANTHROPIC_API_KEY=...
Call
import anthropic
client = anthropic.Anthropic()  # reads ANTHROPIC_API_KEY from env
message = client.messages.create(
    model="claude-fable-5-1",
Model ID
claude-fable-5-1

Request example

import anthropic

client = anthropic.Anthropic()  # reads ANTHROPIC_API_KEY from env
message = client.messages.create(
    model="claude-fable-5-1",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello"}]
)
print(message.content[0].text)

Gotchas

  • Use the versioned model ID, e.g. "claude-sonnet-4-6" or "claude-opus-4-7-20251101".
  • The examples expect ANTHROPIC_API_KEY; rename it only if your application config maps the new variable.

Compare Claude Fable 5.1 Across Providers

ProviderInput (per 1M)Output (per 1M)
Anthropic$10.00$50.00
AWS Bedrock$10.00$50.00
GCP Vertex AI$10.00$50.00
Microsoft Foundry$10.00$50.00

Pricing

TypePrice (per 1M)
Input tokens$10.00
Output tokens$50.00

Capabilities

VisionMultimodalReasoningJSON / Tool useStructured OutputsPrompt CachingBatch API

About Claude Fable 5.1

Anthropic's generally available Mythos-class model for demanding reasoning, long-horizon agents, and ambitious coding, released September 1, 2026. Same underlying model as Claude Mythos 5.1 with cybersecurity and biology safeguards (flagged queries route to Opus 4.8 for cyber and Opus 5 for biology; those reroutes are not billed at Fable prices). Claude API id claude-fable-5-1. List price $10 per 1M input tokens and $50 per 1M output tokens; cache reads $0.25 per 1M (0.025x base input, 75% less than Fable 5's $1.00).

Get Started

Model Specs

Released2026-09-01
Context1m
ArchitectureDecoder Only
Knowledge cutoff2026-06

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