ΔE 8.6, close: similar, with a visible difference side by side. Spiritstone Red is a little darker than Scarlet Red. They are different kinds of paint: AK Interactive Scarlet Red is an opaque base/layer paint and Citadel Spiritstone Red is a technical paint or medium, 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 9). Spiritstone Red is a little darker than Scarlet Red. They are different kinds of paint.
The same difference applies the other way round: Scarlet Red is a little lighter.
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 Scarlet Red on the colour wheel See Spiritstone Red on the colour wheel
All matches: Scarlet Red equivalents · Spiritstone Red equivalents