Claude Fable 5.1 vs DeepSeek-V4 Pro
Source-checked evaluation entries, evidence gaps and checked price quotes where available.
Claude Fable 5.1
Claude Fable 5.1 (Max). Board 2026-10-20; checked 2026-10-22.
Anthropic pricing · checked 2026-10-22. Context tiers and cache-hit rates may differ.
DeepSeek-V4 Pro
DeepSeek-V4-Pro (High, 20260813). Board 2026-10-20; checked 2026-10-22.
DeepSeek pricing · checked 2026-10-22. Context tiers and cache-hit rates may differ.
What the evidence supports
The recorded entries are Claude Fable 5.1 (Max) (1503 ± 6) and DeepSeek-V4-Pro (High, 20260813) (1465 ± 7).
Their point estimates differ by 38 points. The displayed ranges do not overlap; this is not a test of task-specific superiority or a guarantee about a different configuration.
The former composite, MMLU and cost-per-capability recommendations are withdrawn because their inputs included unsupported estimates. No upgrade or overall capability recommendation is made from those numbers.
In the selected standard short-context input quotes, DeepSeek-V4 Pro has the lower rate, by a ratio of 7.58 to one. DeepSeek uses peak pricing. This is input pricing only; it does not estimate a whole workload or establish account access.
Price quotes are from the selected provider registry checked 2026-10-22. Unverified legacy quotes are withheld. Use the token calculator for input, output, cache-hit and context-tier scenarios. Additional service charges and account-specific terms can change a bill. Missing pricing evidence does not mean free inference.
Before choosing a deployment
Use the exact configuration you would deploy on a fixed set of representative tasks. Record accepted answers, failures, end-to-end latency and total metered cost. Check licensing, hosting options and data requirements directly with each provider. This is a proposed evaluation procedure; AI Mastery has not run a head-to-head workload test for this pairing.
The leaderboard records the verified variants and withheld columns. The separate benchmark matrix contains dated provider disclosures and needs its own source/version review.
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