Carbon Black vs Dark Rust

How close are they?

ΔE 12.1, fair: the same colour family, but not a straight swap. Dark Rust is a little lighter, more saturated than Carbon Black.

Can I use Dark Rust instead of Carbon Black?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Dark Rust is a little lighter, more saturated than Carbon Black.

Can I use Carbon Black instead of Dark Rust?

The same difference applies the other way round: Carbon Black is a little darker, more muted.

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.