Ratskin Flesh vs Vulcan Orange

How close are they?

ΔE 15.2, loose: different enough that you should pick on purpose. Vulcan Orange is more saturated, warmer than Ratskin Flesh.

Can I use Vulcan Orange instead of Ratskin Flesh?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Vulcan Orange is more saturated, warmer than Ratskin Flesh.

Can I use Ratskin Flesh instead of Vulcan Orange?

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