Space Green vs Dark Green

How close are they?

ΔE 11.7, fair: the same colour family, but not a straight swap. Dark Green is a little darker, more muted than Space Green.

Can I use Dark Green instead of Space Green?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Dark Green is a little darker, more muted than Space Green.

Can I use Space Green instead of Dark Green?

The same difference applies the other way round: Space Green 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.