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 the density decides how big a label designed in dots comes out on paper.

Mis à jour le 2026-10-20 · Renders made with the OpenZPL engine

Why it matters

ZPL has no centimetres or inches by default: ^FO100,50 means 100 dots from the left and 50 from the top. How long a dot is depends on the printhead. A layout written for one density prints smaller on a denser printer and larger, or cut off, on a coarser one.

Worked example

Dots = millimetres × dpmm. A 100 mm wide label is 800 dots at 8 dpmm and 1,200 dots at 12 dpmm. The same box of 400 × 200 dots is 50 × 25 mm at 8 dpmm and about 33 × 17 mm at 12 dpmm.

Below, the same ZPL rendered on a 4 × 2 in label at both densities. The box keeps its 400 × 200 dots, so it covers less of the label at 12 dpmm.

8 dpmm (203 dpi)

^XA
^FO20,20^GB400,200,4^FS
^FO40,90^A0N,40,40^FD400 x 200 dots^FS
^XZ

12 dpmm (300 dpi)

^XA
^FO20,20^GB400,200,4^FS
^FO40,90^A0N,40,40^FD400 x 200 dots^FS
^XZ

dpmm and dpi

dpi counts dots per inch, dpmm per millimetre; one inch is 25.4 mm. The OpenZPL API and Labelary's take dpmm in the URL (/v1/printers/8dpmm/…) because that is the unit the printhead is built in. See dpi for why 12 dpmm is sold as 300 dpi.

To move a layout between densities, scale every coordinate by the ratio (12 / 8 = 1.5), or write positions in millimetres with ^MU. The guide 203 vs 300 dpi walks through both.