Impish Rouge vs Hot Pink

How close are they?

ΔE 24.3, loose: different enough that you should pick on purpose. Hot Pink is noticeably lighter, much more muted than Impish Rouge.

Can I use Hot Pink instead of Impish Rouge?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 24). Hot Pink is noticeably lighter, much more muted than Impish Rouge.

Can I use Impish Rouge instead of Hot Pink?

The same difference applies the other way round: Impish Rouge is noticeably darker, much more saturated.

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.