Mahogany Brown vs Gorthor Brown

How close are they?

ΔE 15.0, loose: different enough that you should pick on purpose. Gorthor Brown is a little darker, more muted, warmer than Mahogany Brown.

Can I use Gorthor Brown instead of Mahogany Brown?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Gorthor Brown is a little darker, more muted, warmer than Mahogany Brown.

Can I use Mahogany Brown instead of Gorthor Brown?

The same difference applies the other way round: Mahogany Brown is a little lighter, 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.