The layers will be denser as you move from the crust to the inner core.
The density are as the following:
crust (2.55 g/cm³)
upper mantle (3.9 g/cm³)
lower mantle (5 g/cm³)
outer core (11.05 g/cm³)
inner core (12.95 g/cm³)
Thus we can also see that the inner core is the densest layer.
Hope it helps!
