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Claude Fable 5.1 vs DeepSeek V4-Pro

Anthropic against DeepSeek, on sourced numbers only. Green marks the higher (or cheaper) value on each row; the text below only calls a lead when the gap is bigger than measurement noise.

Claude Fable 5.1DeepSeek V4-Pro
Arena Elo1504 source ↗1465 source ↗
GPQA Diamondnot published92.4% source ↗
$ per 1M in / out$10 / $50 source ↗$0.66 / $1.98 source ↗
Blended $ per 1M (3:1)$20.00 source ↗$0.99 source ↗
Context window1M source ↗1M source ↗
Output speednot publishednot published
ReleasedSep 1, 2026 source ↗Aug 13, 2026 source ↗
Open weightsNo source ↗Yes source ↗
Reasoning effort tierslow · medium · high · xhigh · max (default: high)low · high · max (default: high)
API effort controloutput_config={"effort": "low" | "medium" | "high" | "xhigh" | "max"} source ↗thinking={"type": "enabled" | "disabled"}, reasoning_effort="low" | "high" | "max" (medium and xhigh map to high) source ↗
Additional benchmarksTerminal-Bench 4.0: 55.8% source ↗
GDPval-AA v2.1: 1735 source ↗
AA Intelligence Index v5.0.1: 50 source ↗
SWE-bench Verified: 80.6% (April V4 preview card, Max) source ↗
Best for (workload)Anthropic's most capable generally available model, for demanding reasoning and long-horizon agentic work (Anthropic). source ↗Higher GPQA Diamond than V4.1-Flash (92.4% vs 90.9%, DeepSeek); MIT open weights. source ↗

Arena Elo from the arena.ai text leaderboard as of Oct 27, 2026 source ↗. Speed measured by Artificial Analysis and varies by provider.

Which one should I use?

For high-volume work where cost matters most, DeepSeek V4-Pro is about 20.2 times cheaper per token. For overall answer quality as rated by people in blind tests, Claude Fable 5.1 leads clearly (1504 vs 1465 Arena Elo). If you need to self-host or fine-tune, only DeepSeek V4-Pro has open weights. On release timing, Anthropic is at day 30 of a typical ~15-day gap (PAST TYPICAL GAP), and DeepSeek is at day 20 of a typical ~32-day gap (MID-CYCLE).

Key differences from the sourced numbers

Frequently asked questions

Is Claude Fable 5.1 or DeepSeek V4-Pro better?

DeepSeek V4-Pro is the cheaper option: $0.99 vs $20.00 per 1M tokens at a 3:1 input-to-output mix (about 20.2 times less). Claude Fable 5.1 scores 39 Elo points higher (1504 vs 1465) on the Arena text leaderboard, where people vote on blind side-by-side answers. Claude Fable 5.1 pricing note: Same rate across the full 1M context window. DeepSeek V4-Pro pricing note: Off-peak price (cache hit $0.022 / 1M). Peak hours (01:00 to 04:00 and 06:00 to 10:00 UTC, weekdays): $1.32 / $3.96 (cache hit $0.044 / 1M). API continues until V4.1-Pro launches.

Which one should I use: Claude Fable 5.1 or DeepSeek V4-Pro?

For high-volume work where cost matters most, DeepSeek V4-Pro is about 20.2 times cheaper per token. For overall answer quality as rated by people in blind tests, Claude Fable 5.1 leads clearly (1504 vs 1465 Arena Elo). If you need to self-host or fine-tune, only DeepSeek V4-Pro has open weights. On release timing, Anthropic is at day 30 of a typical ~15-day gap (PAST TYPICAL GAP), and DeepSeek is at day 20 of a typical ~32-day gap (MID-CYCLE).

How much does Claude Fable 5.1 cost compared with DeepSeek V4-Pro?

Claude Fable 5.1 lists at $10 / $50 per 1M input/output tokens ($20.00/1M blended at 3:1). DeepSeek V4-Pro lists at $0.66 / $1.98 per 1M input/output tokens ($0.99/1M blended at 3:1).

Anthropic lab hub →DeepSeek lab hub → Compare by effort level & use case → Compare any two models

Facts checked Nov 5, 2026 against official sources. Every number links to its source. Spotted an error? Email [email protected].