QR code size in ZPL

^XA
^FO40,40^BQN,2,5^FDQA,https://zeepler.com/r/A1^FS
^XZ

• ^BQN,2,5: a QR code, normal orientation, model 2 (the current standard, and the one to use), at magnification 5. Magnification runs from 1 to 10 and is the width of one module, the smallest black or white square, in dots.
• QA, at the start of the field data is not printed. Q is the error correction level (about 25% of the code can be damaged and still scan) and A picks the data mode automatically.

The printed width is the number of modules across the code times the magnification. The number of modules depends on the data: this 24-character link at level Q needs a 29 × 29 module code, so magnification 5 prints it 145 dots wide, about 0.71 inch at 203 dpi.

• To make the code bigger or smaller, change the magnification.
• Longer data needs more modules, so the same magnification prints a bigger code. A short link keeps the code small.
• Leave blank space around the code, four modules wide, so a scanner can find its edges.

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    "small": "https://zeepler.com/r/A1",
7    "large": "https://zeepler.com/r/A1"
8  },
9  "templates": [
10    {
11      "type": "QRCode",
12      "dataPath": "small",
13      "coords": [40, 60],
14      "magnification": 3
15    },
16    {
17      "type": "QRCode",
18      "dataPath": "large",
19      "coords": [300, 40],
20      "magnification": 8
21    }
22  ]
23}

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

^XA^MCY^XZ
    ^XA
    ^SZ2
    ^MMT
    ^MNY
    ^LL406
    ^PW812
    ^LH0,0
^BY2,2,0^FO40,60^BQN,2,3^FDQA,https://zeepler.com/r/A1^FS
^BY2,2,0^FO300,40^BQN,2,8^FDQA,https://zeepler.com/r/A1^FS
^XZ

magnification is the same 1 to 10, and zeepler adds the QA, for you. The two codes carry the same link at magnification 3 and 8: 87 and 232 dots wide.

• 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.

• Print and scan the code at the smallest magnification you plan to use, with your own scanners.
• 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.

• Printing ^, ~ and _ in ZPL: Why a caret or tilde in your data cuts the field short, and how ^FH prints them.
• Font size in ZPL: Setting text height with ^A and ^CF, converting points to dots, and why ^CF carries over.
• 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.