ΔE 20.0, loose: different enough that you should pick on purpose. Primary Cyan is a little darker, much more saturated, warmer than Crystal Blue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 20). Primary Cyan is a little darker, much more saturated, warmer than Crystal Blue.
The same difference applies the other way round: Crystal Blue is a little lighter, much 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 Crystal Blue on the colour wheel See Primary Cyan on the colour wheel
All matches: Crystal Blue equivalents · Primary Cyan equivalents