Fluorescent Pink vs Fluorescent Red

How close are they?

ΔE 41.3, loose: different enough that you should pick on purpose. Fluorescent Red is noticeably darker, more saturated, warmer than Fluorescent Pink.

Can I use Fluorescent Red instead of Fluorescent Pink?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 41). Fluorescent Red is noticeably darker, more saturated, warmer than Fluorescent Pink.

Can I use Fluorescent Pink instead of Fluorescent Red?

The same difference applies the other way round: Fluorescent Pink is noticeably lighter, 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.