Font size in ZPL

^XA
^FO40,40^A0N,80,80^FDBin A-12^FS
^FO40,160^A0N,34,34^FDShelf 3, left^FS
^XZ

• ^A0N,80,80: font 0, normal orientation, 80 dots high and 80 wide. It applies to the next field only. Font 0 scales to any size; give it the same width as height for its normal shape, or a smaller width to narrow it.
• ^CF0,40 sets the default font for every field that follows, until the next ^CF. A field with no ^A of its own takes whatever the last ^CF set, which is easy to miss when you move a field.

Dots = points × dpi ÷ 72. A dot is 1/203 inch on a 203 dpi printer and 1/300 inch on a 300 dpi one, so the same ZPL prints smaller on a 300 dpi printer.

Send this body to POST https://api.zeepler.com/v1/zeeplify with your API key in the x-api-key header. It is a working request, not an illustration: on every change, our tests run this same file through the API's code and compare the result with the ZPL below.

1{
2  "config": {
3    "size": "4x2"
4  },
5  "data": {
6    "title": "Bin A-12",
7    "detail": "Shelf 3, left",
8    "note": "Same size as the line above"
9  },
10  "templates": [
11    {
12      "type": "Text",
13      "dataPath": "title",
14      "coords": [40, 40],
15      "font": "0,80"
16    },
17    {
18      "type": "Text",
19      "dataPath": "detail",
20      "coords": [40, 160],
21      "font": "0,34"
22    },
23    {
24      "type": "Text",
25      "dataPath": "note",
26      "coords": [40, 220]
27    }
28  ]
29}

And the ZPL that comes back, ready to send to the printer:

^XA^MCY^XZ
    ^XA
    ^SZ2
    ^MMT
    ^MNY
    ^LL406
    ^PW812
    ^LH0,0
^CF0,80^FO40,40^FDBin A-12^FS
^CF0,34^FO40,160^FDShelf 3, left^FS
^FO40,220^FDSame size as the line above^FS
^XZ

font becomes a ^CF before the field, so it carries over the same way: the third line has no font and prints at 34 dots, like the line above it. Give every Text element a font if you want each one to stay the size you chose when you reorder them.

• Call the API from your own server or integration engine, not from a web page. An API key in a browser is a key anyone can copy.
• A successful call answers 200 with the ZPL as plain text. A request the API cannot turn into a label answers 400 with every problem listed by field, and is not billed.
• Send the ZPL to a Zebra or other ZPL printer at 203 dpi. At 300 dpi the same label prints at two-thirds of the size.

The API reference has every field and status code.

• Text does not wrap. A value longer than the space you left runs off the edge of the label, so set maxLength on any field whose length you do not control.
• Coordinates are in dots from the top-left corner. Print one label, measure it, and adjust: there is no preview.
• Scan every barcode and QR code on a printed label before relying on it.

• QR code size in ZPL: How ^BQ magnification sets the size of a QR code, and how to work out the size in dots.
• Printing ^, ~ and _ in ZPL: Why a caret or tilde in your data cuts the field short, and how ^FH prints them.
• Send ZPL to a Zebra printer from C#: Send ZPL from .NET to a network printer on port 9100, or to a USB printer through the Windows spooler, without the driver redrawing it.