Azure Blue vs Orchid Light

How close are they?

ΔE 16.9, loose: different enough that you should pick on purpose. Orchid Light is a little lighter, more saturated, warmer than Azure Blue.

Can I use Orchid Light instead of Azure Blue?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Orchid Light is a little lighter, more saturated, warmer than Azure Blue.

Can I use Azure Blue instead of Orchid Light?

The same difference applies the other way round: Azure Blue is a little darker, 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.