ZPL and label printing glossary

Short definitions of the terms you meet when designing thermal labels, each with a worked number or picture and how it differs from the term next to it.

Density and size

dpmm (dots per millimetre) dpmm is the print density of a thermal printer in dots per millimetre: 6, 8, 12 or 24 on Zebra printers. Every ZPL coordinate is in dots, so …

dpi (dots per inch) on label printers dpi is the number of dots a printhead prints per inch. Label printers are sold as 152, 203, 300 or 600 dpi, which are rounded names for 6, …

Layout

Field origin The field origin is the point a ZPL field is positioned from. With ^FO it is the top-left corner of the field; with ^FT it is the baseline …

Barcode

Quiet zone The quiet zone is the blank margin a scanner needs on each side of a barcode to find where it starts and ends. ZPL doesn't add it for …

Check digit A check digit is the last digit of a barcode number, computed from the others so a scanner can detect a misread. EAN-13 and UPC-A always have one; …

Images

Z64 image encoding Z64 is a compressed way to send image data in ZPL: the bitmap is compressed with zlib (deflate), encoded in Base64 and followed by a CRC checksum. It …