Dark Wood vs Blackened Brown

How close are they?

ΔE 10.0, close: similar, with a visible difference side by side. Blackened Brown is cooler than Dark Wood. They are different kinds of paint: Army Painter Dark Wood is a one-coat contrast-style paint and Reaper Blackened Brown is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.

Can I use Blackened Brown instead of Dark Wood?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Blackened Brown is cooler than Dark Wood. They are different kinds of paint.

Can I use Dark Wood instead of Blackened Brown?

The same difference applies the other way round: Dark Wood is warmer.

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.