Model Comparison

A.x K2 vs Fable 5.1

A.x K2 ranks #92 on the AI IQ leaderboard with an estimated IQ of 104, while Fable 5.1 ranks #4 on the AI IQ leaderboard with an estimated IQ of 138. 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
A.x K2World (Other)Fable 5.1Anthropic
Rank#92#4
IQ104138
Abstract Reasoning86124
Mathematical Reasoning94149
Academic Reasoning124137
Programmatic Reasoning101147
Computer Use100142
Reliability112136
Knowledge Work108133
Emotional Reasoning——
Effective Cost / 1M Tokens—$89.32
Sticker Price / 1M I/O Tokens—$60.00
Speed—61 tok/s
Context Window262K1M
Released2026-07-292026-09-01
Open WeightsYesNo