Red Oxide vs Faded Red

How close are they?

ΔE 17.4, loose: different enough that you should pick on purpose. Faded Red is noticeably lighter, more muted, cooler than Red Oxide.

Can I use Faded Red instead of Red Oxide?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Faded Red is noticeably lighter, more muted, cooler than Red Oxide.

Can I use Red Oxide instead of Faded Red?

The same difference applies the other way round: Red Oxide is noticeably darker, more saturated, 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.