Art Black vs Infantry Blue

How close are they?

ΔE 9.8, close: similar, with a visible difference side by side. Infantry Blue is a little darker, more saturated than Art Black.

Can I use Infantry Blue instead of Art Black?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Infantry Blue is a little darker, more saturated than Art Black.

Can I use Art Black instead of Infantry Blue?

The same difference applies the other way round: Art Black 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.