ΔE 17.0, loose: different enough that you should pick on purpose. N8 Neutral Gray is a little lighter, much more muted than Frost Blue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). N8 Neutral Gray is a little lighter, much more muted than Frost Blue.
The same difference applies the other way round: Frost Blue is a little 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.
See Frost Blue on the colour wheel See N8 Neutral Gray on the colour wheel
All matches: Frost Blue equivalents · N8 Neutral Gray equivalents