German Sand Beige RAL 8031 vs Dark Sand

How close are they?

ΔE 6.5, close: similar, with a visible difference side by side. Dark Sand is a little darker than German Sand Beige RAL 8031.

Can I use Dark Sand instead of German Sand Beige RAL 8031?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Dark Sand is a little darker than German Sand Beige RAL 8031.

Can I use German Sand Beige RAL 8031 instead of Dark Sand?

The same difference applies the other way round: German Sand Beige RAL 8031 is a little lighter.

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.