ΔE 8.5, close: similar, with a visible difference side by side. Acid Green is a little darker, more saturated than Militarum Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Acid Green is a little darker, more saturated than Militarum Green.
The same difference applies the other way round: Militarum Green 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 Militarum Green on the colour wheel See Acid Green on the colour wheel
All matches: Militarum Green equivalents · Acid Green equivalents