# Quiet zone

Source: https://openzpl.com/glossary/quiet-zone/ (updated 2026-10-20)

The quiet zone is the blank margin a scanner needs on each side of a barcode to find where it starts and ends. ZPL doesn't add it for you: a barcode placed at x = 0 starts at the very edge of the label.

## How big it should be

Linear barcodes need at least 10 times the narrow bar width on each side; GS1 asks for more on EAN and UPC. In ZPL the narrow bar is the first ^BY parameter, in dots. With ^BY3 the minimum is 30 dots: 3.75 mm at 8 dpmm, 2.5 mm at 12 dpmm.

| Narrow bar (^BY) | Quiet zone (10×) | At 8 dpmm | At 12 dpmm |
|---|---|---|---|
| 2 | 20 dots | 2.5 mm | 1.7 mm |
| 3 | 30 dots | 3.75 mm | 2.5 mm |
| 4 | 40 dots | 5 mm | 3.3 mm |

QR codes need four modules of margin and Data Matrix one module, in their own module size.

## Before and after

No quiet zone: ^FO0,60:
```zpl
^XA
^BY3,3,140
^FO0,60^BCN,140,Y,N,N
^FDOZ-0042^FS
^XZ
```

80 dots of margin: ^FO80,60:
```zpl
^XA
^BY3,3,140
^FO80,60^BCN,140,Y,N,N
^FDOZ-0042^FS
^XZ
```

The left render looks fine on screen, but on paper the first bar is at the cut of the label, and printer registration can move it a millimetre either way. Scanners often fail on that side only, which makes the problem look random.

## Quiet zone and label margin

A label margin keeps ink away from the edge for the printer's sake; the quiet zone is for the scanner and also applies between a barcode and a box line or another field. See barcode not scanning for the other causes.