ΔE 9.4, close: similar, with a visible difference side by side. IDF Sand Grey is a little lighter, warmer than Ghoul Skin.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). IDF Sand Grey is a little lighter, warmer than Ghoul Skin.
The same difference applies the other way round: Ghoul Skin is a little darker, 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 Ghoul Skin on the colour wheel See IDF Sand Grey on the colour wheel
All matches: Ghoul Skin equivalents · IDF Sand Grey equivalents