Claude Fable 5.1 vs DeepSeek Flash (4.1)
Claude Fable 5.1 scores higher on the Models at Work leaderboard (80 vs 70 out of 100). DeepSeek Flash (4.1) is about 38× cheaper per blended million tokens ($0.52 vs $20).
| Claude Fable 5.1 · Anthropic | DeepSeek Flash (4.1) · DeepSeek | |
|---|---|---|
| Leaderboard rank | #6 | #9 |
| Score (0–100) | 80 | 70 |
| Tier | Frontier | Fast and cheap |
| Price per 1M tokens | $10 in · $50 out | $0.30 in · $1.20 out |
| Context window | 1M | 1M |
| Open weights | No | Not verified |
| Artificial Analysis Intelligence Index | 53 | — |
| Arena text score | 1501 | — |
| Humanity's Last Exam, Diamond (Scale) | 51.3 | — |
| Best for | Long-horizon agents, Problems Opus fails on, Demanding reasoning | Cheap coding tiers, Bulk generation, Experiments where data residency is not a constraint |
Choose Claude Fable 5.1 if…
- you need long-horizon agents
- you need problems opus fails on
- you need demanding reasoning
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.
Caveats: Ten dollars per million input is the highest in this table alongside Astra.
Choose DeepSeek Flash (4.1) if…
- you need cheap coding tiers
- you need bulk generation
- you need experiments where data residency is not a constraint
The reason a thousand people argued on Hacker News this week: frontier-adjacent coding for pocket change, with the caveats you would expect.
Caveats: Open-weights status and licence not verified from a primary source at time of writing. Off-peak and peak pricing differ; the cheap numbers are off-peak. Data handling terms should be read before any enterprise use.
What practitioners say
DeepSeek Flash (4.1): The 'why isn't the industry freaking out' post hit 1,067 points; the most-upvoted replies say the price is real and the coding gap to Opus is also real.
Questions people ask
Which is better, Claude Fable 5.1 or DeepSeek Flash (4.1)?
Claude Fable 5.1 scores higher on the Models at Work leaderboard (80 vs 70 out of 100). DeepSeek Flash (4.1) is about 38× cheaper per blended million tokens ($0.52 vs $20).
When should I choose Claude Fable 5.1 over DeepSeek Flash (4.1)?
Choose Claude Fable 5.1 for long-horizon agents, problems opus fails on, demanding reasoning. 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.
When should I choose DeepSeek Flash (4.1) over Claude Fable 5.1?
Choose DeepSeek Flash (4.1) for cheap coding tiers, bulk generation, experiments where data residency is not a constraint. The reason a thousand people argued on Hacker News this week: frontier-adjacent coding for pocket change, with the caveats you would expect.
Which is cheaper, Claude Fable 5.1 or DeepSeek Flash (4.1)?
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). DeepSeek Flash (4.1) costs $0.30 per million input tokens and $1.20 per million output tokens on DeepSeek's list price (DeepSeek API pricing, read Oct 10, 2026).
Scores come from the Models at Work leaderboard: 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. Prices are vendor list prices where published; blended figures assume three input tokens per output token.