ΔE 15.0, fair: the same colour family, but not a straight swap. Macragge Blue is a little lighter, more saturated, warmer than Deep Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Macragge Blue is a little lighter, more saturated, warmer than Deep Blue.
The same difference applies the other way round: Deep Blue is a little darker, 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.
See Deep Blue on the colour wheel See Macragge Blue on the colour wheel
All matches: Deep Blue equivalents · Macragge Blue equivalents