Claude Fable 5.1
The specialist: Anthropic's own docs say to reach for it when Opus 5.5 at high effort still falls short, and the price says the same.
Key facts
- Score
- 80 / 100, rank #6
- Price
- $10 in · $50 out per 1M tokens (Claude pricing)
- Blended price
- $20 per 1M tokens (3 input : 1 output)
- Context window
- 1M
- Open weights
- No
- Best for
- Long-horizon agents, Problems Opus fails on, Demanding reasoning
Claude Fable 5.1 costs $10 per million input tokens and $50 per million output tokens on Anthropic's list price (Claude pricing, read Oct 10, 2026).
Independent evals
| Benchmark | Result | Who ran it | Read |
|---|---|---|---|
| Artificial Analysis Intelligence Index (max) | 53 | Artificial Analysis LLM leaderboard | Oct 9, 2026 |
| Arena text score (max) | 1501 | Arena text leaderboard (Oct 8, 2026) | Oct 9, 2026 |
| Humanity's Last Exam, Diamond (Scale) | 51.3 | Scale SEAL leaderboards | Oct 9, 2026 |
Caveats
- Ten dollars per million input is the highest in this table alongside Astra.
Questions people ask
How much does Claude Fable 5.1 cost?
Claude Fable 5.1 costs $10 per million input tokens and $50 per million output tokens on Anthropic's list price (Claude pricing, read Oct 10, 2026).
How good is Claude Fable 5.1?
Claude Fable 5.1 ranks #6 of 12 on the Models at Work leaderboard with a score of 80 out of 100 (October 2026 edition). The specialist: Anthropic's own docs say to reach for it when Opus 5.5 at high effort still falls short, and the price says the same.
What is Claude Fable 5.1 best for?
Claude Fable 5.1 is best for long-horizon agents, problems opus fails on, demanding reasoning.
What are Claude Fable 5.1's benchmark scores?
Artificial Analysis Intelligence Index (max): 53 (Artificial Analysis LLM leaderboard); Arena text score (max): 1501 (Arena text leaderboard (Oct 8, 2026)); Humanity's Last Exam, Diamond (Scale): 51.3 (Scale SEAL leaderboards).
What is Claude Fable 5.1's context window?
Claude Fable 5.1 has a 1M token context window according to Anthropic.
Is Claude Fable 5.1 open weights?
No. Claude Fable 5.1 is a proprietary model available through Anthropic's API and partner clouds.
Compare Claude Fable 5.1
- Claude Fable 5.1 vs Claude Opus 5.5
- Claude Fable 5.1 vs GPT-6 Astra
- Claude Fable 5.1 vs Gemini 4 Argon
- Claude Fable 5.1 vs Claude Sonnet 5.5
- Claude Fable 5.1 vs GPT-6.1 Sol
- Claude Fable 5.1 vs Claude Haiku 5.5
- Claude Fable 5.1 vs Muse Spark 1.3
- Claude Fable 5.1 vs DeepSeek Flash (4.1)
- Claude Fable 5.1 vs GPT-6 Luna
- Claude Fable 5.1 vs Kimi K3
- Claude Fable 5.1 vs Grok 4.7
Methodology: Score is 0 to 100: 50% independent evals normalised within this table, 20% price-performance, 15% practitioner sentiment from Signals and community threads, 15% operational fit (context, speed, availability, open weights). Models within three points are a tie in practice. Vendor-published figures are labelled as such and never counted as independent.