ΔE 12.5, fair: the same colour family, but not a straight swap. Light Grey is a little lighter, more muted than Brown Gray.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Light Grey is a little lighter, more muted than Brown Gray.
The same difference applies the other way round: Brown 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 Brown Gray on the colour wheel See Light Grey on the colour wheel
All matches: Brown Gray equivalents · Light Grey equivalents