ΔE 6.1, close: similar, with a visible difference side by side. Airbrush Thinner is more muted than Offwhite.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Airbrush Thinner is more muted than Offwhite.
The same difference applies the other way round: Offwhite is 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 Offwhite on the colour wheel See Airbrush Thinner on the colour wheel
All matches: Offwhite equivalents · Airbrush Thinner equivalents