ΔE 9.2, close: similar, with a visible difference side by side. Light Brown is a little darker, more saturated than Ruddy Fur. They are different kinds of paint: Army Painter Ruddy Fur is a one-coat contrast-style paint and Green Stuff World Light Brown is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Light Brown is a little darker, more saturated than Ruddy Fur. They are different kinds of paint.
The same difference applies the other way round: Ruddy Fur is a little lighter, more muted.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Ruddy Fur on the colour wheel See Light Brown on the colour wheel
All matches: Ruddy Fur equivalents · Light Brown equivalents