What is a "printer class"?
Every printer you register has a printer_class in addition to its transport. The class tells the Printing service what physical paper the printer uses, which in turn drives the CSS width and page geometry of the rendered chit, receipt, or label. Pick the class that matches your actual hardware — picking the wrong one produces layouts that are cut off or wasted on oversized paper.
Supported classes
| Class | Paper width | CSS width | Typical use |
|---|---|---|---|
| Thermal 80mm | 80 mm | 72 mm | Kitchen chits, host chits, standard receipts. The most common restaurant / retail class. |
| Thermal 58mm | 58 mm | 50 mm | Compact handheld or mobile receipt printers. Shorter line length, smaller footer. |
| Label 2x1 in | 51 mm | 51 mm | Shelf labels, name tags, asset labels. Single-block layout, no multi-line runs. |
| Letter (8.5 x 11) | 216 mm | 8 in | Reservation confirmations, customer profile cards, HCM paperwork. North American office printers. |
| A4 | 210 mm | 210 mm | Same as Letter but for regions using ISO paper sizes. |
How templates pick a class
Each print template declares a default printer class. For example, queue.chit defaults to Thermal 80mm, while reservations.confirmation defaults to Letter. If you route a job to a printer whose class differs from the template default, the template still renders at the printer's class — so a queue.chit sent to a Letter printer produces a centered, full-page chit rather than a narrow receipt strip.
Mixing classes in one org
You can register as many printers of as many classes as you need. A typical single-site restaurant has one Thermal 80mm for the expo, one Thermal 58mm at the host stand, and one Letter for office paperwork — all under the same Printing license.