Amaranth Red vs Nomad Flesh

How close are they?

ΔE 15.5, loose: different enough that you should pick on purpose. Nomad Flesh is a little lighter, much more muted than Amaranth Red.

Can I use Nomad Flesh instead of Amaranth Red?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Nomad Flesh is a little lighter, much more muted than Amaranth Red.

Can I use Amaranth Red instead of Nomad Flesh?

The same difference applies the other way round: Amaranth Red is a little darker, much more saturated.

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.