ΔE 17.1, loose: different enough that you should pick on purpose. Flat Earth is a little lighter, much more saturated than N2 Neutral Gray.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Flat Earth is a little lighter, much more saturated than N2 Neutral Gray.
The same difference applies the other way round: N2 Neutral Gray is a little darker, much 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.
See N2 Neutral Gray on the colour wheel See Flat Earth on the colour wheel
All matches: N2 Neutral Gray equivalents · Flat Earth equivalents