ΔE 10.9, fair: the same colour family, but not a straight swap. Grey Brown is a little lighter, warmer than Olivegrove Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Grey Brown is a little lighter, warmer than Olivegrove Green.
The same difference applies the other way round: Olivegrove Green is a little darker, 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 Olivegrove Green on the colour wheel See Grey Brown on the colour wheel
All matches: Olivegrove Green equivalents · Grey Brown equivalents