Reddish Orange vs Flat Red

How close are they?

ΔE 12.8, fair: the same colour family, but not a straight swap. Flat Red is a little darker, more muted than Reddish Orange.

Can I use Flat Red instead of Reddish Orange?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Flat Red is a little darker, more muted than Reddish Orange.

Can I use Reddish Orange instead of Flat Red?

The same difference applies the other way round: Reddish Orange is a little lighter, more saturated.

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.