ΔE 13.2, fair: the same colour family, but not a straight swap. BS Dark Earth is a little darker, much more muted, warmer than Green Brown.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). BS Dark Earth is a little darker, much more muted, warmer than Green Brown.
The same difference applies the other way round: Green Brown is a little lighter, much more saturated, cooler.
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 Green Brown on the colour wheel See BS Dark Earth on the colour wheel
All matches: Green Brown equivalents · BS Dark Earth equivalents