Vermillion vs Rust

How close are they?

ΔE 12.1, fair: the same colour family, but not a straight swap. Rust is a little darker, more muted, warmer than Vermillion.

Can I use Rust instead of Vermillion?

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

Can I use Vermillion instead of Rust?

The same difference applies the other way round: Vermillion is a little lighter, more saturated, cooler.

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.