How to Print Shipping Labels at the Right Size
Why labels come out the wrong size, how to set up your printer, and how to protect barcodes from being distorted.
A label that prints at the wrong size can be rejected by a carrier, or may not scan at all. Nearly always, the cause is a scaling setting rather than the label itself.
Know your label and your printer
- Thermal label printers usually take 4 × 6 inch (about 100 × 150 mm) labels and print at 203 or 300 DPI. Many can print right up to the edge.
- Office printers use A4 or Letter paper and have margins they cannot print on. Several labels may fit on one sheet, but only if they are not reduced too far.
The setting that causes most problems
In the print dialog, choose Actual size or 100%, not Fit to page. Fit to page quietly resizes everything, including the barcode. Also check that the paper size in the dialog matches the paper in the printer.
Crop before you print
Marketplaces often supply a label in the corner of a full page. Printing that page on a thermal printer shrinks the whole sheet to fit, so the label comes out tiny. Crop it to the label first, then print at full size.
Protect the barcode
- Do not stretch a label in one direction only. Keep the proportions the same.
- Leave the blank margin around the barcode, known as the quiet zone. Scanners need it.
- Avoid enlarging a small image. It cannot add detail, and the edges of the bars will blur.
- Use a dark, fresh print: faded thermal or low-toner output is a common cause of failed scans.
Always test first
Print one label, measure it with a ruler, and scan the barcode with a phone or scanner before printing a whole batch. No tool can guarantee that a barcode will scan after being changed, and your carrier's rules always take priority.