Phalanx Blue vs Interior Blue Soviet

How close are they?

ΔE 11.4, fair: the same colour family, but not a straight swap. Interior Blue Soviet is a little lighter, warmer than Phalanx Blue.

Can I use Interior Blue Soviet instead of Phalanx Blue?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Interior Blue Soviet is a little lighter, warmer than Phalanx Blue.

Can I use Phalanx Blue instead of Interior Blue Soviet?

The same difference applies the other way round: Phalanx Blue is a little darker, 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.