Clay Brown vs Chaotic Red

How close are they?

ΔE 6.3, close: similar, with a visible difference side by side. Chaotic Red is a little darker than Clay Brown.

Can I use Chaotic Red instead of Clay Brown?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Chaotic Red is a little darker than Clay Brown.

Can I use Clay Brown instead of Chaotic Red?

The same difference applies the other way round: Clay Brown is a little lighter.

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.