Model Comparison

Fable 5.1 vs Lfm2.5 2.6b

Fable 5.1 ranks #4 on the AI IQ leaderboard with an estimated IQ of 138, while Lfm2.5 2.6b ranks #155 on the AI IQ leaderboard with an estimated IQ of 84. 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 5.1AnthropicLfm2.5 2.6bUS (Other)
Rank#4#155
IQ13884
Abstract Reasoning12478
Mathematical Reasoning14977
Academic Reasoning13795
Programmatic Reasoning14779
Computer Use14276
Reliability13690
Knowledge Work13392
Emotional Reasoning——
Effective Cost / 1M Tokens$89.32—
Sticker Price / 1M I/O Tokens$60.00—
Speed61 tok/s—
Context Window1M131K
Released2026-09-012026-08-04
Open WeightsNoYes