ΔE 9.8, close: similar, with a visible difference side by side. Green Ink is a little lighter, more muted than Ghoul Green. They are different kinds of paint: Army Painter Ghoul Green is a one-coat contrast-style paint and Formula P3 Green Ink is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Green Ink is a little lighter, more muted than Ghoul Green. They are different kinds of paint.
The same difference applies the other way round: Ghoul Green is a little darker, 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.
See Ghoul Green on the colour wheel See Green Ink on the colour wheel
All matches: Ghoul Green equivalents · Green Ink equivalents