Khardic Flesh vs Ferrari Red

How close are they?

ΔE 23.0, loose: different enough that you should pick on purpose. Ferrari Red is noticeably darker, more saturated, cooler than Khardic Flesh.

Can I use Ferrari Red instead of Khardic Flesh?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Ferrari Red is noticeably darker, more saturated, cooler than Khardic Flesh.

Can I use Khardic Flesh instead of Ferrari Red?

The same difference applies the other way round: Khardic Flesh is noticeably lighter, 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.