The symbol for dishwasher safe is not universal, but there are several symbols that can indicate that an item is safe to wash in the dishwasher. Some even provide recommended rack placement and drying instructions. The most common symbol for dishwasher safe is a square box with some plates or glasses (or both) inside it. This is true for both top rack and generally dishwasher safe items. You’ll also see either water droplets or diagonal lines that are meant to signify water. For items that are only "top rack only," the droplets or diagonal lines will only hit the top of the plates or glasses. If the symbol just shows droplets or lines that cross the entirety of the square box, it’s probably safe to wash the item on either the top or bottom rack. The image may also include a temperature to clarify the safest top temperature you can use on the item.