Sandy Yellow vs Fairy Flesh

How close are they?

ΔE 9.8, close: similar, with a visible difference side by side. Fairy Flesh is a little lighter, more muted than Sandy Yellow.

Can I use Fairy Flesh instead of Sandy Yellow?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Fairy Flesh is a little lighter, more muted than Sandy Yellow.

Can I use Sandy Yellow instead of Fairy Flesh?

The same difference applies the other way round: Sandy Yellow 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.