ΔE 13.8, fair: the same colour family, but not a straight swap. Azure Blue is a little darker, more muted, warmer than Ionic Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Azure Blue is a little darker, more muted, warmer than Ionic Blue.
The same difference applies the other way round: Ionic Blue is a little lighter, more saturated, 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 Ionic Blue on the colour wheel See Azure Blue on the colour wheel
All matches: Ionic Blue equivalents · Azure Blue equivalents