ZPL / TSPL generator and mm ↔ dots converter

Thermal printers measure in dots, not millimetres. Convert your sizes, then generate the code for a simple label to send to a Zebra printer (ZPL II) or a TSC or compatible printer (TSPL).

Millimetres ↔ dots converter

Millimetres ⇄ Dots Resolution

Common sizes in dots

Size	203 dpi	300 dpi
100 × 150 mm	799 × 1199	1181 × 1772
4 × 6″	812 × 1218	1200 × 1800
103 × 199 mm	823 × 1590	1217 × 2350
100 × 100 mm	799 × 799	1181 × 1181
57 × 32 mm	456 × 256	673 × 378
50 × 25 mm	400 × 200	591 × 295
40 × 30 mm	320 × 240	472 × 354

ZPL / TSPL code generator

Layout preview

Approximate preview: the printer uses its own fonts and draws the real barcodes.

Dots and resolution

A 203 dpi printer prints 8 dots per millimetre, a 300 dpi printer about 11.8. A 100 mm wide label is therefore 799 dots at 203 dpi and 1,181 dots at 300 dpi. ZPL and TSPL give every position in dots, so the same code printed on a printer with another resolution comes out smaller or larger.

Sending the code to the printer

From software or a script: send the text as-is to the printer port (USB, or network port 9100).
With the manufacturer’s utility: most can send a command file (.zpl, .prn).
The printer must run the chosen language: ZPL for Zebra and “ZPL-compatible” models, TSPL for TSC and many generic printers.

Limits

The generator covers a simple layout: text lines, one barcode and a frame. The commands follow the ZPL II and TSPL programming manuals, but the output has not been tested on every model: run a test before a large batch. TSPL text uses the built-in bitmap fonts; accented characters depend on the printer’s code page.

To check that a roll suits your model, use the printer compatibility checker.