ΔE 12.2, fair: the same colour family, but not a straight swap. Dark Green is more saturated, warmer than Cobalt Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Dark Green is more saturated, warmer than Cobalt Green.
The same difference applies the other way round: Cobalt Green is more muted, 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 Cobalt Green on the colour wheel See Dark Green on the colour wheel
All matches: Cobalt Green equivalents · Dark Green equivalents