How much string light does a balcony need? Drape it and see

A string of lights always needs more length than the gap it spans, because it sags. Plan it before you buy: set your balcony width, the number of swags and how deep they hang, and see the lit length, bulb count, hooks and the set length to look for.

Drag the dot to change the dip, and see why more hooks with the same dip means more string. No picks here, just the measuring.