Model Comparison

Fable 5.1 vs Sonnet 5

Fable 5.1 ranks #5 on the AI IQ leaderboard with an estimated IQ of 137, while Sonnet 5 ranks #27 on the AI IQ leaderboard with an estimated IQ of 125. The table below puts the two models side by side across the seven capability dimensions, emotional reasoning, cost, speed, and context window.

Fable 5.1 profile →Sonnet 5 profile →

First model Second model

Where They Sit on the IQ Bell Curve

Both models highlighted on the standard normal IQ distribution of every tracked model

IQ Dimensions Head to Head

The seven scored Composite IQ dimensions, side by side

Domains Head to Head

Applied domain composite scores where at least one model is measured

	Fable 5.1Anthropic	Sonnet 5Anthropic
Rank	#5	#27
IQ	137	125
Abstract Reasoning	124	105
Mathematical Reasoning	148	131
Academic Reasoning	136	129
Programmatic Reasoning	147	131
Computer Use	140	129
Reliability	135	123
Knowledge Work	133	124
Emotional Reasoning	—	117
Effective Cost / 1M Tokens	$90.82	$38.51
Sticker Price / 1M I/O Tokens	$60.00	$12.00
Speed	68 tok/s	82 tok/s
Context Window	1M	1M
Released	2026-09-01	2026-06-30
Open Weights	No	No

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