ΔE 10.2, fair: the same colour family, but not a straight swap. White Grey is a little lighter, more muted than J.N. Gray.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). White Grey is a little lighter, more muted than J.N. Gray.
The same difference applies the other way round: J.N. Gray is a little darker, 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 J.N. Gray on the colour wheel See White Grey on the colour wheel
All matches: J.N. Gray equivalents · White Grey equivalents