What would be a good resolution for background images?

I am making an rpg that will have drawn backgrounds + sprites (sort of like Star Ocean 2). What would be the best resolution for background images so they look as nice as possible without been too heavy?

For art assets I’ve found in the past the best way to work is to generate the assets at a larger size than you think you will need them (so for backgrounds, quite large) then you can selectively reduce the size that unity imports them at later on based on your performance needs. That way you can always scale down if you need easily, but you avoid the hard tast of scaling assets up without them looking bad.

As for size specifically, depends on your target device, I’d say most of the time 2048 is a reasonable top limit to aim at for a background image then adjusting import settings down as required.