Model Comparison

Fable 5.1 vs Fable 5.2

Fable 5.1 ranks #7 on the AI IQ leaderboard with an estimated IQ of 138, while Fable 5.2 ranks #1 on the AI IQ leaderboard with an estimated IQ of 144. The table below puts the two models side by side across the seven capability dimensions, emotional reasoning, cost, speed, and context window.

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 5.1AnthropicFable 5.2Anthropic
Rank#7#1
IQ138144
Abstract Reasoning124134
Mathematical Reasoning147148
Academic Reasoning135135
Programmatic Reasoning147154
Computer Use145157
Reliability136145
Knowledge Work132134
Emotional Reasoning——
Effective Cost / 1M Tokens$92.11$73.69
Sticker Price / 1M I/O Tokens$60.00$48.00
Speed70 tok/s—
Context Window1M1M
Released2026-09-012026-11-09
Open WeightsNoNo