Printing a 4 × 6 label on an ordinary A4 printer

Conversion produces one page per label, and each page is exactly the size you chose on screen. Choose 101.6 × 152.4 mm and the PDF has 101.6 × 152.4 mm pages, not A4 pages with a label in the middle.

What the file declares plays no part in that. A file can carry ^PW and ^LL describing the size:

^XA
^PW812
^LL1218
^FO50,50^A0N,30,30^FDPedido 1234^FS
^XZ

And that changes nothing on conversion: we measured with and without, and the output is identical. The field on screen is what decides the page size. The guide on ignored commands explains why the choice was made that way.

In the print dialog, find the scaling option. It usually arrives ticked as "Fit to page" or "Shrink oversized pages", and that tick is what ruins the label.

Choose "Actual size" or "100% scale". The label will come out small in the corner of an A4 sheet, and that is exactly right: it measures 4 × 6 inches, and the sheet measures 8.3 × 11.7.

The reason is the barcode. "Fit to page" enlarges the label until it fills the sheet, roughly doubling the width of every bar. A scanner calibrated for the original bar starts misreading, and the defect is treacherous because the label visibly looks better: bigger, crisper, and unreadable to a machine.

Print one label and measure its width with a ruler. If you chose 101.6 mm, the printed label has to measure 10.1 cm. If it measures 14, 15 or 20, scaling is switched on somewhere.

That ten-second test beats any setting you verify on screen, because scaling can be applied in three different places: the PDF reader, the printer driver, and the printer's own panel. The ruler measures the result of all three together.

The "multiple pages per sheet" option (2-up, 4-up) saves paper and shrinks the label, which has the same effect as scaling up, only in reverse: the bars end up thinner than the printer can lay down accurately.

If the barcode is never read by a machine, and plenty of operations only need a legible address, 2-up works fine. If it is read, print one per sheet. A thermal label printer solves the problem outright, and it is the route for anyone shipping every day.

Full-sheet adhesive A4 or Letter paper exists and is the most practical option: print, cut around the label, stick it on. You do not need paper pre-cut to 4 × 6, because the PDF does not use the whole sheet anyway.

If you do use pre-cut sheets with ready divisions, check the division sizes first: the PDF has no idea where the perforations are, and it draws the label in the corner of the sheet. Aligning the two is manual work, and it usually costs more than cutting.