ΔE 10.5, fair: the same colour family, but not a straight swap. Off-White is a little darker, more saturated than Zinc White.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Off-White is a little darker, more saturated than Zinc White.
The same difference applies the other way round: Zinc White 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.
See Zinc White on the colour wheel See Off-White on the colour wheel
All matches: Zinc White equivalents · Off-White equivalents