Bright Coral vs Medium Flesh

How close are they?

ΔE 21.1, loose: different enough that you should pick on purpose. Medium Flesh is noticeably lighter, much more muted, warmer than Bright Coral.

Can I use Medium Flesh instead of Bright Coral?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Medium Flesh is noticeably lighter, much more muted, warmer than Bright Coral.

Can I use Bright Coral instead of Medium Flesh?

The same difference applies the other way round: Bright Coral is noticeably darker, much more saturated, 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.