ΔE 8.6, close: similar, with a visible difference side by side. Chalice Red is a little lighter, cooler than Dark Brown.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Chalice Red is a little lighter, cooler than Dark Brown.
The same difference applies the other way round: Dark Brown is a little darker, 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.
See Dark Brown on the colour wheel See Chalice Red on the colour wheel
All matches: Dark Brown equivalents · Chalice Red equivalents