ΔE 30.7, loose: different enough that you should pick on purpose. Magenta is much more saturated, warmer than Dead Purple.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 31). Magenta is much more saturated, warmer than Dead Purple.
The same difference applies the other way round: Dead Purple is 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 Dead Purple on the colour wheel See Magenta on the colour wheel
All matches: Dead Purple equivalents · Magenta equivalents