Rainfall Blue vs Runic Cobalt

How close are they?

ΔE 10.4, fair: the same colour family, but not a straight swap. Runic Cobalt is a little lighter, more muted than Rainfall Blue.

Can I use Runic Cobalt instead of Rainfall Blue?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Runic Cobalt is a little lighter, more muted than Rainfall Blue.

Can I use Rainfall Blue instead of Runic Cobalt?

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