Anthropic: Claude Fable 5.1
The Anthropic: Claude Fable 5.1 is a large language model that supports various input modalities, including text, image, and file inputs. It has a maximum context length of 1000000 tokens and can generate output up to 128000 tokens. When evaluating this model for your needs, consider its pricing structure, which charges $10 per million input tokens and $50 per million output tokens. Its benchmark performance is also worth noting, with a blended score of 100 across one independent benchmark, suggesting it is capable of robust reasoning and structured output.
Benchmark results
Independent, published benchmarks. Blended score 92.0 across 1 benchmark, last refreshed 2026-10-13. How scoring works →
| Benchmark | Measures | Score |
|---|---|---|
| AI Index | broad capability composite | 88.0 |
- Model ID
- anthropic/claude-fable-5.1
- Vendor
- anthropic
- Released
- September 2026
- Tokenizer
- Claude
- Input Modalities
- text, image, file
- Output Modalities
- text
- Max Output
- 128,000 tokens
- Tool Calling
- ✓ supported
- Structured Output
- ✓ supported
- Reasoning Mode
- ✓ supported
- Vision
- ✓ accepts images
- Audio
- no
- Moderated
- yes
What it costs in practice
Computed from the current $10.00/M input and $50.00/M output rates. Run your own numbers →
| Job | Tokens | Cost |
|---|---|---|
| Summarize a 50-page report | 30k in / 1.5k out | $0.38 |
| Classify 1,000 customer emails | 500k in / 50k out | $7.50 |
| A month of a busy support chatbot | 5M in / 2M out | $150.00 |
Similar models
Anthropic: Claude Fable 5
Anthropic: Claude Opus 4.1 (batch)
Anthropic: Claude Opus 4.1
Anthropic: Claude Fable 5.1 (batch)
Anthropic: Claude Opus 5
Anthropic: Claude Fable 5 (batch)
Quick answers
- How much does Anthropic: Claude Fable 5.1 cost?
- $10.00 per million input tokens and $50.00 per million output tokens.
- What is Anthropic: Claude Fable 5.1's context window?
- 1,000,000 tokens, roughly 1,500 pages of text in a single request.
- Does Anthropic: Claude Fable 5.1 support tool calling?
- It supports tool calling, structured output, a reasoning mode.
- Can Anthropic: Claude Fable 5.1 process images?
- Yes, it accepts image input.