Claude Fable 5.1
Claude Fable 5.1 costs $10 per 1M input tokens and $50 per 1M output tokens. Its context window is 1,000,000 tokens. Claude Fable 5.1 has no announced retirement. Anthropic says it will not retire it before Sep 1, 2027. Checked 2026-10-21.
"For demanding reasoning and long-horizon agentic work"
Facts
| API model ID | claude-fable-5-1 | Source |
|---|---|---|
| Vendor | Anthropic | Source |
| Input price | $10 per 1M tokens | Source |
| Output price | $50 per 1M tokens | Source |
| Cached input price | $0.25 per 1M tokens | Source |
| Context window | 1,000,000 tokens | Source |
| Max output | 128,000 tokens | Source |
| Inputs | Text, Images | Source |
| Released | Sep 1, 2026 | Source |
| Knowledge cutoff | Jun 2026 | Source |
| Retirement | Active. Anthropic says not retired before Sep 1, 2027. | Source |
Anthropic's most capable model open to all customers. Cache hits cost 0.025x the input price.
What replaces it, and what it replaces
- Anthropic has not named a replacement.
- For older models that already have shutdown dates, see our AI model retirement dates calendar.
Benchmark scores
Independent scores from Epoch AI, which scores every vendor's models the same way. The rank compares Claude Fable 5.1 with the other models on our AI models page.
| Benchmark | Claude Fable 5.1 |
|---|---|
| Epoch Capabilities Index One score that combines many benchmarks, such as math, science, and coding tests, into a single scale. Epoch sets Claude 3.5 Sonnet at 130 and GPT-5 at 150. | 166.49 Rank 4 of 17 models here |
| GPQA Diamond 198 hard multiple-choice questions in biology, chemistry, and physics, written by PhD-level experts. Guessing scores 25%. We show the highest score for each model across the reasoning settings Epoch ran. | No score listed |
Scores are Epoch AI's, not ours. Source: Epoch AI, Capabilities and benchmarking, from its public data download, checked 2026-10-21. Used under CC BY 4.0. We drew the charts. A benchmark is one test, so run your own inputs before you choose.
What it costs for your workload
At 10,000 requests a month of 5,000 input and 500 output tokens, Claude Fable 5.1 costs about $975 a month. Change the numbers to match yours.
Monthly cost estimate
Example sizes are our round numbers. Set your own below.
Claude Fable 5.1 $975 a month
$98 per 1,000 requests
List prices checked 2026-10-21, standard tier, no caching, no batch discount. Claude 4.7 and later count about 30% more tokens for the same text, so their rows include that. Long-prompt prices apply where the vendor sets them.
Compare it
- Claude Fable 5.1 vs GPT-6 Astra
- Compare Claude Fable 5.1 with any other model
- Not sure which model fits the job? The AI model picker gives you three to test.
Questions clients ask
Short answers, no sales language. If yours isn't here, ask an engineer directly.
Ask us anythingHow much does Claude Fable 5.1 cost?
$10 per 1M input tokens and $50 per 1M output tokens at list price. At 10,000 requests a month of 5,000 input and 500 output tokens, that is about $975 a month. Checked 2026-10-21.
What is the context window of Claude Fable 5.1?
1,000,000 tokens, with up to 128,000 output tokens per request.
When will Claude Fable 5.1 be retired?
No retirement is announced. Anthropic says retirement will be no sooner than Sep 1, 2027, and it gives at least 60 days' notice.
Can Claude Fable 5.1 read images or PDFs?
Anthropic lists these inputs: text, images. PDF is not listed as an input type on the model page.
Building on Claude Fable 5.1?
We add models to products and test them on your real inputs. We bill hourly or by milestone.