Rust Brown vs Fire Red

How close are they?

ΔE 11.7, fair: the same colour family, but not a straight swap. Fire Red is noticeably darker, more muted than Rust Brown.

Can I use Fire Red instead of Rust Brown?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Fire Red is noticeably darker, more muted than Rust Brown.

Can I use Rust Brown instead of Fire Red?

The same difference applies the other way round: Rust Brown is noticeably 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.