Light Gray (IJN) vs Cement Grey

How close are they?

ΔE 10.8, fair: the same colour family, but not a straight swap. Cement Grey is a little darker, more saturated than Light Gray (IJN).

Can I use Cement Grey instead of Light Gray (IJN)?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Cement Grey is a little darker, more saturated than Light Gray (IJN).

Can I use Light Gray (IJN) instead of Cement Grey?

The same difference applies the other way round: Light Gray (IJN) is a little lighter, more muted.

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.