Shipping Barcode Labels

Shipping Label Basics

Carrier-generated shipping labels (FedEx, UPS, USPS, DHL, Amazon) contain proprietary barcodes — Code 128, PDF417, and DataMatrix — that encode tracking numbers, routing codes, and service levels specific to each carrier's network. You cannot generate these carrier barcodes yourself; they must come from the carrier's API or label printing service.

What you can design and print locally are supplementary labels: internal tracking labels, packing list barcodes, return labels using your own order ID, and outbound labels for internal routing before handover to the carrier. These use standard barcodes (Code 128 is most common) encoding your own order or shipment reference.

4″ × 6″ Thermal Label Setup

The 4″ × 6″ (101.6 × 152.4 mm) label is the carrier standard. Thermal label printers — Zebra, Dymo, Rollo, MUNBYN, and others — are designed around this size. Design your label in the label maker above using the thermal 4×6 template, then print directly from your browser or export PNG at 203 or 300 DPI for the thermal driver.

Keep the barcode in the lower half of the label, with recipient address and any human-readable text in the upper half. This follows carrier convention and ensures the barcode is not obscured by packaging tape applied across the top.

Printing Quality for Shipping Labels

Direct thermal printing at 203 DPI is the minimum acceptable quality for shipping barcodes. Most modern thermal printers default to 300 DPI, which is sufficient. Thermal transfer printing (using a ribbon) produces more durable labels and is preferred for packages that will sit in a facility for extended periods before shipment.

Never print shipping barcodes on an inkjet printer unless you are using waterproof ink. Standard inkjet ink runs when wet, destroying the barcode mid-transit. Laser printing on label stock is acceptable for low-volume shipping.

Frequently Asked Questions