ΔE 14.2, fair: the same colour family, but not a straight swap. Putrid Green is a little darker, more saturated than Olive Drab.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Putrid Green is a little darker, more saturated than Olive Drab.
The same difference applies the other way round: Olive Drab 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 Olive Drab on the colour wheel See Putrid Green on the colour wheel
All matches: Olive Drab equivalents · Putrid Green equivalents