ΔE 13.6, fair: the same colour family, but not a straight swap. Toxic Boils is noticeably lighter, more saturated, cooler than Purple INK. They are different kinds of paint: AK Interactive Purple INK is an ink, glaze or transparent paint and Army Painter Toxic Boils is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Toxic Boils is noticeably lighter, more saturated, cooler than Purple INK. They are different kinds of paint.
The same difference applies the other way round: Purple INK is noticeably darker, more muted, 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 Purple INK on the colour wheel See Toxic Boils on the colour wheel
All matches: Purple INK equivalents · Toxic Boils equivalents