ΔE 8.3, close: similar, with a visible difference side by side. US Earth Brown is a little darker, more muted than Drab Brown.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). US Earth Brown is a little darker, more muted than Drab Brown.
The same difference applies the other way round: Drab Brown is a little lighter, more saturated.
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 Drab Brown on the colour wheel See US Earth Brown on the colour wheel
All matches: Drab Brown equivalents · US Earth Brown equivalents