Open Top

An open top has no fastening: the mouth of the bag stays open, and access takes one motion with one hand. Large totes, market bags, beach bags and most shoppers are built this way because the shape is the point rather than an omission.

Nothing has to fit through a closure, so tall and irregular items go straight in. A rolled umbrella, a bunch of celery, a laptop in a hard case, a poster tube: anything you would have to angle past a zip simply drops in. Loading and unloading run faster than with any other closure. A bag used at a desk or in a car is often better left open.

What you gain in speed you pay in exposure. Rain falls straight in, the contents sit in plain view of anyone standing beside you, and a bag knocked off a chair empties completely. One zipped interior pocket is close to essential, and a bag without one should be sized down or skipped. Side height helps as well. An open bag under 11 inches tall lets a bottle stand proud of the rim. Taller sides keep contents below the opening and out of sight. Some designs add a single magnetic tab or a snap at the center as a compromise. That pulls the sides together to stop the worst gaping without adding a real fastening.