IJN Hull Color/Kure vs USN Light Ghost Grey

How close are they?

ΔE 7.3, close: similar, with a visible difference side by side. USN Light Ghost Grey is a little lighter than IJN Hull Color/Kure.

Can I use USN Light Ghost Grey instead of IJN Hull Color/Kure?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). USN Light Ghost Grey is a little lighter than IJN Hull Color/Kure.

Can I use IJN Hull Color/Kure instead of USN Light Ghost Grey?

The same difference applies the other way round: IJN Hull Color/Kure is a little darker.

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.