Rust vs Mephiston Red

How close are they?

ΔE 13.2, fair: the same colour family, but not a straight swap. Mephiston Red is more saturated, cooler than Rust.

Can I use Mephiston Red instead of Rust?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Mephiston Red is more saturated, cooler than Rust.

Can I use Rust instead of Mephiston Red?

The same difference applies the other way round: Rust is more muted, 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.