Recommendation: A QR Code that encodes up to 72 characters (which is the length of a typical URL) should be printed in a size of 20×20 mm (0.79x0.79″) when scanned from a distance of 20cm (7.9″)
||QR Code Size
|A4 e.g. Magazine
||20mm x 20mm
|A3 e.g. Poster
||100mm x 100mm
|3x4m e.g. Billboard
||1m x 1m
Before applying this recommendation please consider the following tips. If you you are printing a designer QR Code please also read Printing QR Codes with Colors.
Consider the scanning distance
Rule of the thumb: the ratio between scanning distance and the QR Code size is 10:1. So if you want to scan a QR Code from 10 meters (390″), the size of the QR Code should be 1 square meter (39″). Or if you print a QR Code on a post card, the user will scan the QR Code from a distance close to 15cm (5.9″). Applying the rule the QR Code may have a minimum size of 15mm (0.59″).
Quiet Zone around the QR Code
Have at least a Quiet Zone of 4 Units arround your QR Codes.
If you print a QR Code always leave a quite zone (margin) around the QR Code. We recommend to have 4 units of white space arround your QR Code to ensure it can be read by any QR Code reader.
Use shorted URLs
How much information do you want to store in the QR Code? The less the better. Use shortened URLs instead of a long URL. The shorter the URL the less units a QR Code will contain and there for can be plotted smaller.
A shortened URL with up to 17 characters will produce a QR Code with 21×21 units. Encoding a longer URL with up to 72 chars will result in a QR Code with 35×35 units.
A shorted URL: http://qrd.by/t
Use low Error Correction Level
When creating a QR Code you can set an Error Correction Level. The higher the level is set, the more of a QR Code may be destroyed while the QR Code will be still readable. However, a higher level also increases the size of a QR Code. We recommend setting the error level L for QR Codes without an embedded logo. This will give you the smallest possible size of a QR Code. The following figure shows you a QR Code with the same encoded URL in two different error correction levels:
|Level L 7%
||Level H 30 %
Use scale able vectorized QR Codes
It is important create QR Codes in Vector format. If you are plotting QR Codes from a .png or .jpg source, they may get blurred and cannot be read anymore.
Create optimized QR Code
Download the QR Code Contest .pdf document and print it out. It contains various QR Codes in different sizes. In theory you will be able to scan QR Codes with a size of 5mm (0.19″), depending on your printer and your scanning device. If you are able to scan QR Codes in an even smaller size, please let us know!!!
Devices that scan QR Codes < 4mm (0.16”)
Huawei Ascend XT H1611 (3mm QR Code was printed on a Canon MF4320 laser printer with 600dpi)
Devices that scan QR Codes < 5mm (0.19”)
Apple iPhone 5
Google Nexus 5
Huawei Ascend Mate 7
LG D802, D959
Nokia Lumia 635
Samsung GALAXY ACE 3, GALAXY Note 4 Edge, GALAXY S4, GT-I9500, SGH-I317
Sony Xperia Z1
Xiaomi MI 2SC