Why does my label print blank?

The usual causes are the thermal paper being loaded upside down (the printable side faces the print head), the wrong paper size so content is placed off the media, or a driver that expects a different orientation.

Why is my label shrunk with white borders?

Scaling is enabled in the print dialog, or the PDF page is larger than 4x6 so the driver fits it to the media. Split the PDF into exact 4x6 pages and print at 100%.

Printing

How to Print Shipping Labels on a 4×6 Thermal Printer

Most “my label printed wrong” problems are not label problems. They are three settings in the print dialog and one sheet of paper loaded the wrong way round. Here is the short version, then the troubleshooting.

The settings that matter

Setting	Correct value	What goes wrong otherwise
Paper size	4 × 6 in / 101.6 × 152.4 mm	Content is laid out for Letter and the bottom of the label is cut off
Scale	100% / Actual size	“Fit to page” shrinks the label, bars get thinner, scans fail
Orientation	Portrait for 4×6, landscape for 6×4	The label prints rotated 90° and the address block falls off the media
Margins	None / default driver margin	Extra margins push the label down and clip the barcode
Media type	Direct thermal label / gap-sensing label	The printer feeds past the gap or stops mid-label

Is your PDF still Letter-sized? Split it into exact 4×6 pages first, then print at 100%.

Open the splitter

Step by step

Open the PDF in your browser's viewer and press the print shortcut, or use the print button in the viewer.
Choose the thermal printer, not a desktop inkjet.
Set the paper size to the label stock. If 4×6 is missing, the driver does not know the media — set a custom size of 4 × 6 in in the printer preferences.
Set scale to 100% and switch off “Fit to page”, “Shrink to fit” or “Scale to fit”.
Look at the print preview. The label should fill the page edge to edge; a preview with wide white borders means something is being rescaled.
Print one label before a batch, and scan it with the same scanner your carrier uses.

Five things that go wrong, and what they mean

1. The label prints completely blank

Direct thermal paper only prints on one side. If the roll is loaded with the printable face away from the print head, the result is a blank label with no error message. Flip the roll and try again.

2. Only half the label prints

The PDF page is bigger than the media. A 612 × 792 pt page sent to 4×6 stock loses everything outside the 288 × 432 pt area — usually the bottom half. Split the PDF into 4×6 pages instead of printing a Letter page onto label stock.

3. Everything is tiny with a white frame

Scaling is on, or the driver is “fitting” a large page onto small media. Turn off fit-to-page and confirm the page is exactly 4×6.

4. The label prints but the barcode will not scan

Three causes, in order of likelihood: the label was rescaled below 100%; the barcode was cropped and lost its quiet zone; the print density is too low for the paper. Check the crop first, then raise darkness one step.

5. The printer feeds two labels and stops

The printer is not sensing the gap between labels. Run the printer's own calibration (usually holding the feed button until it blinks), and make sure the media type is set to label/gap, not continuous.

Why exact page size beats “it looks fine in the preview”

A driver prints a 612 × 792 pt page onto 4×6 media by scaling or clipping — and which one it does depends on the driver, not on the PDF. When the page is already 288 × 432 pt, there is nothing to fit or clip, so every driver behaves the same way. That is the whole reason to split before printing rather than after.

Printer-specific notes

Rollo, Zebra, Brother and Munbyn all ship their own drivers and utilities, and the menu names differ between versions. This guide deliberately sticks to the settings that exist in every print dialog rather than naming menus that may have moved. If a setting is missing in your driver, it is usually in the printer's own preferences dialog, which the operating system shows as “Properties” or “Preferences” next to the printer name.

Questions

Can I print several labels on one long roll?

Yes — send the whole PDF at once. Each page becomes one label, and the printer feeds them continuously. Print one first to confirm the size.

Does the paper brand matter?

For scanning, yes. Very thin or low-grade direct thermal paper produces fainter bars and fades faster. If your labels scan poorly in summer, the paper is a likely cause.

Do I need special software?

No. Any PDF viewer that can print at 100% works. The only tool you need is something that produces 4×6 pages in the first place.