Use a keyring or a small paperclip as a temporary zipper pull. For a permanent fix, swap the broken pull tab with a new one by sliding it into place. Squeeze it closed gently with a pair of pliers.

Got a broken zipper box? You can fix that with 3D printing. Mystified about how zippers work? No need to be.

But let's not get ahead of ourselves as it isn't always an easy fix. In fact, broken zippers are arguably the most awkward fashion piece to repair. The more you try and move the slider up and down ...