Copper vs Ruby Red

How close are they?

ΔE 15.0, fair: the same colour family, but not a straight swap. Ruby Red is a little lighter, more saturated, cooler than Copper.

Can I use Ruby Red instead of Copper?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Ruby Red is a little lighter, more saturated, cooler than Copper.

Can I use Copper instead of Ruby Red?

The same difference applies the other way round: Copper is a little 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.