Dark DAK Sand vs Bone Khaki

How close are they?

ΔE 23.0, loose: different enough that you should pick on purpose. Bone Khaki is noticeably lighter, much more muted than Dark DAK Sand.

Can I use Bone Khaki instead of Dark DAK Sand?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Bone Khaki is noticeably lighter, much more muted than Dark DAK Sand.

Can I use Dark DAK Sand instead of Bone Khaki?

The same difference applies the other way round: Dark DAK Sand is noticeably darker, much 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.