ΔE 8.7, close: similar, with a visible difference side by side. Fire Red is a little darker, more muted than Ruddy Terra.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Fire Red is a little darker, more muted than Ruddy Terra.
The same difference applies the other way round: Ruddy Terra is a little lighter, more saturated.
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 Ruddy Terra on the colour wheel See Fire Red on the colour wheel
All matches: Ruddy Terra equivalents · Fire Red equivalents