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Anthropic

Claude Fable

#2of 28 · general

Fable 5.1

1Mcontext
$10 / $50per 1M in / out
2026-09-01released
50100Coding 80 · #5 of 28Agents 83 · #3 of 29Cyber 43 · #3 of 24Engineering 74 · #5 of 26Math 87 · #1 of 26Health 86 · #3 of 24Legal 84 · #2 of 27Professional 86 · #3 of 28Writing 83 · #1 of 21Instruct 66 · #5 of 25Hallucination 53 · #7 of 26Multimodal 74 · #5 of 24
Coding80#5
Agents83#3
Cyber43#3
Engineering74#5
Math87#1
Health86#3
Legal84#2
Professional86#3
Writing83#1
Instruct66#5
Hallucination53#7
Multimodal74#5

History

ECI163.2163.4163.6163.8164.0164.2164.4Jul 2026Claude Fable 5 · $10/M in · 2026-06-09 · still served · Epoch Capabilities Index 163.4 ECI pointsClaude Fable 5.1 · $10/M in · 2026-09-01 · still served · Epoch Capabilities Index 164.2 ECI points5
  • Anthropic
  • older → newer
$ / M input tokens2 of 176 priced models · price is a third-party claim, not a vendor quote

Effort

Fable 5.1
% of best score80901000.5×0.7×1×1.5×× the best effort’s cost · log scaleLowMedHighXhighMax

Measured

≈ imputed · amber dot = lab-self-reported among the sources
GPQA Diamond93.4%#7Vals.ai
HLE59.1%#2Artificial AnalysisEpoch AILLM Stats
MMLU-Pro92.4%#1Vals.ai
LiveBench83.4%#1LiveBench
LiveCodeBench90.5%#1Vals.ai
SciCode63.1%#2Artificial AnalysisEpoch AI
CritPt31.1%#5Artificial AnalysisEpoch AI
Terminal-Bench85.0%#3Vals.ai
APEX Agents68.6%#4Epoch AI
GDPval62.8%#4Artificial Analysis
Arena1501#3Arena
AA Index53.4#5Artificial Analysis
Vals Index65.8#4Vals.ai
Epoch Capabilities Index166.5#4Epoch AI

Neighbors

Gemini Argon→ follows instructions better · cheaperClaude Opus→ more factual · cheaperGPT Astra→ more factualMuse Wonder→ weaker multimodal · cheaperClaude Sonnet→ cheaper