Weight class
The shipping weight tier a seller assigns to an item, also called a weight category, which determines what the buyer pays for shipping.
On Whatnot, sellers assign each item a weight class, sometimes called a weight category, and that tier determines the shipping cost the buyer sees at checkout. A single trading card, a one-pound box of comics, and a pair of boots sit in different classes and price differently to ship.
Getting weight classes right matters in both directions. Set them too heavy and your items look expensive next to identical items on another seller's show. Set them too light and the difference between what the buyer paid and what the postage actually costs can land on you. Weigh your common item types once, set honest classes, and your shipping economics stay boring in the best way.
There is a second reason to get this right, and it surprises people: an item with no weight class has nothing to buy postage against, so its shipping label may never generate at all. If an order is sitting in awaiting shipment with no label to print, the weight class is the first thing to check. Our guide on Whatnot label printing problems covers that case and the other reasons a label fails to appear.