Anthropic: Claude Fable 5.1

anthropic · Released Sep 1, 2026 TOP PICK
DFO score #3 / 698
88.1 leaderboard score
Speed #221 / 338
67.1 tok/s
Input Price #677 / 698
$10.00 per 1M tokens
Output Price #682 / 698
$50.00 per 1M tokens
Context #97 / 698
1M tokens

Analysis Summary

Claude Fable 5.1 is Anthropic's flagship Fable model in this batch, with leading measured reasoning and coding capability and strong agentic results. It supports a one-million-token context, image and file input, tool use, and function calling. That combination is well suited to complex tasks that require long-context analysis, software work, or multiple tool-driven steps.

For an agency, it can support coding agents, long-document review, and client-facing content tasks where instruction following and quality matter. Vision and file input extend its usefulness beyond text-only workflows. The key trade-off is cost: listed input and output prices make it a premium choice for routine, high-volume requests.

Use Fable 5.1 for work where depth and reliability justify the spend, and route simpler tasks to a lower-cost model.

Assessed September 23, 2026

Editorial notes

Claude Fable 5.1 pairs leading reasoning and coding results with strong agentic performance, a one-million-token context, vision, and tool calling, making it suited to demanding client workflows.

The DFO score ranks models on the Artificial Analysis Intelligence Index and is refreshed as new models launch. The write-up and verdict are our own. Feedback?

DFO Verdict

Claude Fable 5.1 pairs leading reasoning and coding results with strong agentic performance, a one-million-token context, vision, and tool calling, making it suited to demanding client workflows.

#3 of 698 overall

Benchmarks

Intelligence Index 53.4 #3 of 436 · Artificial Analysis
Coding Index 81.6 #1 of 198 · Artificial Analysis
Agentic Index 57.9 #2 of 181 · Artificial Analysis
Creative Writing 1,484 #6 of 64 · Arena rating
Instruction Following 1,498 #5 of 65 · Arena rating

Artificial Analysis data refreshed Oct 12, 2026. Arena ratings from the Oct 2, 2026 text leaderboard, with style control.

How Anthropic: Claude Fable 5.1 compares

Anthropic: Claude Fable 5.1 ranks #3 of 436 AI models we track for overall intelligence, #1 of 198 for coding, #2 of 181 for agentic tasks. Its 1M-token context window is larger than 86% of the models we list. At $10.00 per million input tokens it is cheaper than 3% of comparable models.

Position in the field
DFO score: ahead of 100% of models #3
Speed: faster than 35% of models #221
Price: cheaper than 3% of models #677
Context: larger than 86% of models #97
worst in fieldmedianbest in field
Price vs frontier peers · $ per 1M tokens
Anthropic: Claude Fable 5.1 $10.00 in $50.00 out
Anthropic: Claude Opus 5.5 $4.00 in $20.00 out
Anthropic: Claude Sonnet 5.5 $2.00 in $10.00 out
OpenAI: GPT-6 Astra $10.00 in $50.00 out

Dark bar = input · light bar = output, scaled to the priciest peer.

Context window vs peers · tokens

1M tokens ≈ 8 full-length novels or ~2,500 pages of business documents in a single request.

Pricing

Token Type Cost per 1M tokens Cost per 1K tokens
Input $10.00 $0.010000
Output $50.00 $0.050000

What would Anthropic: Claude Fable 5.1 cost your business?

Pick the job that looks most like yours, then fine-tune with the sliders. Estimates update live.

A website chatbot handling around 100 customer conversations a day, a few short messages each.

3,000
One request is one message, email, draft or automation call.
1,200 tokens

$79.20/mo Anthropic: Claude Fable 5.1 $0.03 per request
$31.68/mo Anthropic: Claude Opus 5.5 $0.01 per request
$15.84/mo Anthropic: Claude Sonnet 5.5 · best value $0.0053 per request

Full calculator with 698 models → Price Calculator

DFO AI AUTOMATION

These numbers get smaller with the right architecture.

We route routine calls to cheap models and save Anthropic: Claude Fable 5.1 for the hard ones. Most clients cut their estimate by 60-80%.

Talk to our team

About Anthropic: Claude Fable 5.1

Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual..

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Frequently asked questions about Anthropic: Claude Fable 5.1

How much does Anthropic: Claude Fable 5.1 cost?

Anthropic: Claude Fable 5.1 costs $10.00 per million input tokens and $50.00 per million output tokens.

What is the context window of Anthropic: Claude Fable 5.1?

Anthropic: Claude Fable 5.1 has a context window of 1,000,000 tokens (1M).

Is Anthropic: Claude Fable 5.1 good for coding?

On our coding benchmark index, Anthropic: Claude Fable 5.1 ranks #1 of 198 models, placing it in the top quartile of the field for code generation and debugging.

What can Anthropic: Claude Fable 5.1 do?

Anthropic: Claude Fable 5.1 supports image/vision input, tool use, and function calling.

Who created Anthropic: Claude Fable 5.1?

Anthropic: Claude Fable 5.1 is developed by Anthropic and was released on September 1, 2026.

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