claude-opus-5
Input price$5
Output price$25
AnthropicTextVision
claude-fable-5.1
claude-fable-5.1 is Anthropic's model at $10.00 input and $50.00 output per million tokens, with a 1000K context window. On a typical 3:1 input-to-output mix that blends to roughly $20.00 per million tokens, placing it in the premium band of the 76 models tracked here — cheaper than 0% of them.
Context window1000K
Input price$10 / 1M
Output price$50 / 1M
Output speed—
Quality score—
Data updatedUpdated Sep 2026
Price verified2026-09-02 · Official
Price noteCache hits are $0.25 / 1M tokens — 0.025x base input, against the 0.1x every other Claude model uses. Batch is 50% off ($5 / $25)
By price, claude-fable-5.1 ranks 73rd cheapest of 76 on input and 74th on output.. Its blended rate sits 565% above the catalog average.
In real billing terms: a support chatbot handling 50,000 turns a month (2,000 input / 500 output tokens each) costs about $2,250 per month on claude-fable-5.1, while a RAG workload of 20,000 queries (8,000 input / 800 output tokens each) runs about $2,400. Because output is priced 5.0× input here, long-generation tasks scale cost fastest — cap output length before you optimise anything else.
A 1000K context window holds roughly 1,333 pages of A4 text (at ~750 tokens per page), ranking 25th of 76 here. That is enough to drop in an entire technical manual or several source files at once, which suits long-document summarization and codebase-wide analysis.
We track 9 Anthropic models, and claude-fable-5.1's blended rate sits 76% above that provider's average. If your task tolerates a little less headroom, Phi-4-mini (Microsoft) blends about 100% cheaper at a quality score of 68, and is worth benchmarking first. Going the other way, Phi-4 scores 76 on quality for about 100% less.
The closest model in Anthropic's line-up is claude-fable-5 ($10.00 input / $50.00 output, quality 96). Against it, claude-fable-5.1 scores 96 points lower on quality, has a 49K smaller context window. When two models sit this close on price, the deciding factor is usually the quality ceiling — run both against your real prompts before picking.
Estimated monthly cost
Monthly API spend across four common workloads, next to the cheapest model we track.
| Workload | Usage assumption | This model | Cheapest model |
|---|---|---|---|
| Support chatbot | 2,000 input / 500 output tokens per turn, 50,000 turns per month | $2,250 | $3.00 |
| RAG document Q&A | 8,000 input / 800 output tokens per query, 20,000 queries per month | $2,400 | $3.84 |
| Coding assistant | 12,000 input / 2,000 output tokens per request, 10,000 requests per month | $2,200 | $3.20 |
| Batch summarization | 4,000 input / 400 output tokens per item, 200,000 items per month | $12,000 | $19 |
Derived directly from the rates on this page. Excludes prompt caching, batch discounts and free tiers.
How it compares
The alternatives worth benchmarking alongside it, from the same dataset.
| Model | Provider | Blended /1M | Quality | Price delta |
|---|---|---|---|---|
| claude-fable-5.1 | Anthropic | $20.00 | — | — |
| Phi-4-miniCheaper option | Microsoft | $0.025 | 68 | -100% |
| Phi-4Higher quality | Microsoft | $0.088 | 76 | -100% |
| claude-fable-5Same provider | Anthropic | $20.00 | 96 | +0% |
Best for
CodingReasoningLong Context
Modalities
TextVision
Where it fits — and where it doesn't
Good fit
- Coding: writing, refactoring and debugging across multi-file project context.
- Reasoning: multi-step decomposition, planning and tasks that need rigorous inference.
- Long documents: a 1000K window ingests a full contract, paper or large codebase in one pass.
- Multimodal input: handles images, screenshots and scanned documents directly.
Poor fit
- High-frequency batch jobs: at $20.00 blended per million tokens, bills scale quickly at volume.
Frequently asked questions
How much does the claude-fable-5.1 API cost?
claude-fable-5.1 costs $10.00 per million input tokens and $50.00 per million output tokens. On a 3:1 input-to-output mix that blends to about $20.00 per million tokens.
What does claude-fable-5.1 cost per month?
It depends on volume. Using the four worked scenarios on this page: a support chatbot runs about $2,250/month, RAG document Q&A about $2,400/month, a coding assistant about $2,200/month, and batch summarization about $12,000/month. Plug your own token counts into the cost calculator for a tailored figure.
How large is the claude-fable-5.1 context window?
1000K tokens — roughly 1,333 pages of A4 text at ~750 tokens per page, ranking 25th of the 76 models tracked here.
claude-fable-5.1 or Phi-4-mini — which is better value?
Phi-4-mini blends to about $0.025 per million tokens versus $20.00 for claude-fable-5.1 — roughly 100% cheaper — at a quality score of 68 against —. If that quality gap does not show up on your task, take the cheaper one; if it does, stay with claude-fable-5.1. Benchmark both on your own data before deciding.
What is claude-fable-5.1 best suited for?
Tagged use cases: coding, reasoning, long-context. Coding: writing, refactoring and debugging across multi-file project context. Less suitable: High-frequency batch jobs: at $20.00 blended per million tokens, bills scale quickly at volume.
How current is this claude-fable-5.1 pricing?
Pricing here was last verified on 2026-09-02 against official documentation. llmprice.app runs a daily collection job, but providers can change rates between runs — confirm against Anthropic's official pricing page before you commit.
Estimate the real cost of this model
Bring tokens per request and monthly volume into the calculator to compare total model costs.
Related models
Continue by provider and use case.
View model
claude-opus-4-8
Input price$5
Output price$25
claude-opus-4-6
Input price$5
Output price$25
Pricing, speed and quality scores change over time. Confirm official documentation before production use.