Abyssal Blue vs Ultramarine Blue

How close are they?

ΔE 11.6, fair: the same colour family, but not a straight swap. Ultramarine Blue is more saturated, warmer than Abyssal Blue.

Can I use Ultramarine Blue instead of Abyssal Blue?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Ultramarine Blue is more saturated, warmer than Abyssal Blue.

Can I use Abyssal Blue instead of Ultramarine Blue?

The same difference applies the other way round: Abyssal Blue is more muted, 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.