ΔE 13.5, fair: the same colour family, but not a straight swap. Fluor Red is a little lighter, more saturated than Flesh Tearers Red. They are different kinds of paint: Citadel Flesh Tearers Red is a one-coat contrast-style paint and Green Stuff World Fluor Red is a fluorescent or effect 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 13). Fluor Red is a little lighter, more saturated than Flesh Tearers Red. They are different kinds of paint.
The same difference applies the other way round: Flesh Tearers Red is a little darker, more muted.
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 Flesh Tearers Red on the colour wheel See Fluor Red on the colour wheel
All matches: Flesh Tearers Red equivalents · Fluor Red equivalents