ΔE 12.6, fair: the same colour family, but not a straight swap. Gorgon Brown is a little darker, more muted, warmer than Ruby Red.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Gorgon Brown is a little darker, more muted, warmer than Ruby Red.
The same difference applies the other way round: Ruby Red is a little lighter, more saturated, 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 Ruby Red on the colour wheel See Gorgon Brown on the colour wheel
All matches: Ruby Red equivalents · Gorgon Brown equivalents