ΔE 7.8, close: similar, with a visible difference side by side. Dusty Skull is a little lighter, cooler than Matt Dirt. They are different kinds of paint: AMMO by Mig Matt Dirt is an ink, glaze or transparent paint and Army Painter Dusty Skull is an opaque base/layer 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 8). Dusty Skull is a little lighter, cooler than Matt Dirt. They are different kinds of paint.
The same difference applies the other way round: Matt Dirt is a little darker, warmer.
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 Matt Dirt on the colour wheel See Dusty Skull on the colour wheel
All matches: Matt Dirt equivalents · Dusty Skull equivalents