Different couriers may prefer different sizes, so you must check with them before creating your shipping labels. The majority of the biggest shipping couriers in the US, like UPS, FedEx, and USPS, normally require shipping labels to be 4 x 6 inches.
Rectangular shipping labels are typically around 2¾” x 3½”, while square shipping labels are usually 2″ x 2″. If you’re looking for something more durable or waterproof, you can also find labels with these features online. You can print out these standard sizes using direct thermal printers or through standard printers.