Cadian Fleshtone vs Blackert Brown

How close are they?

ΔE 8.3, close: similar, with a visible difference side by side. Blackert Brown is more muted, warmer than Cadian Fleshtone.

Can I use Blackert Brown instead of Cadian Fleshtone?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Blackert Brown is more muted, warmer than Cadian Fleshtone.

Can I use Cadian Fleshtone instead of Blackert Brown?

The same difference applies the other way round: Cadian Fleshtone is more saturated, cooler.

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.