QR codes are becoming more popular than ever. The latest indicator is that Google has now updated its Chrome for iOS browser to include a QR code scanner for devices such as the Apple iPhone 7 Plus. Google’s move reflects the growing use of QR codes with apps such as Snapchat, Messenger and Kik and by retailers such as Amazon. The Walmart Pay app, for instance, now lets customers pay by holding their phone over a QR code, enabling shoppers to check out faster without ever having to reach into their wallet. With the increasing popularity of QR codes, you may be thinking of adopting them for your brick-and-mortar store or website. Here are a few best practices you’ll need to follow to ensure that your QR code use translates into a positive experience for your customers and your business.
Resolution and Size
Your customer’s mobile device must be able to read your QR code accurately in order to use it, so image resolution is important. A smartphone camera’s ability to read a QR code is determined by the distance the camera is held from the code as well as the size of the dots in the code. The more information a code contains, the smaller the dots become. In other words, the longer the URL for the web page that your QR code directs to, the harder the code is to read. This means it’s a good idea to use URL shorteners.
As a rough rule of thumb, the relationship between scan distance and readable code size is about 10:1, so that, for instance, a 1 inch by 1 inch code could be read from about 10 inches away. Within these parameters, the dots must still be large enough to be read. The more rows and columns of data your code includes, the harder it becomes to read. QR codes generally start with around 21 rows and columns. For every additional 4 rows and columns, the code becomes denser by a factor of 1. Assuming a 3 or 4 megapixel camera, each dot should be no less than 0.016 inches (0.4 mm) across. You can figure out your dot size by taking the width of your code and dividing by the number of rows. To make your dots large enough, you can either reduce the number of dots it contains by shortening your URL to 60 characters or less, or alternately, you can increase the size of your code.
Resolution can be lost through resizing if you use certain formats. Due to this factor, PNG is an ideal code format to maintain image quality, since resizing a PNG image does not affect its resolution. SVG is also a good format for the same reason. You can also generate a QR code in JPEG or PDF format, but bear in mind that you may lose quality if you resize. Don’t stretch or otherwise distort your code when resizing.
QR code provider Unitag recommends not making codes smaller than 1.2 square inches (3 square centimeters). However, it is possible to make codes smaller and still readable if they contain sufficiently short URLs. This is sometimes done for business cards, for example.
To illustrate some typical code sizes, Unitag offers its free users the ability to print QR Codes in PNG format at 300 pixels, which is about the smallest size you should use. But since higher resolution is better, Unitag’s premium plans allow PNG codes up to 3,000px.
For human readers, you should include margins around your code to make them easier to see. Use a margin about one-eighth of an inch.
QR codes become difficult to read on very reflective or curved surfaces. To avoid reflection problems and provide sufficient contrast, codes should be printed in a dark color on white or soft pastel backgrounds. QR scanners use the three dark corners of codes as reference points, so the color contrast between these corners and your background.
Make sure your codes are easy to see and scan. Generally, this means putting your code on or near the top of a box. For example, your customer should not have to turn a heavy item upside-down in order to see or scan your code. Providing instructions on how to use the code is also recommended.
QR codes direct to a website, and since your customer will be using a mobile device, your website should be mobile-friendly. Make sure you test your site for mobile compatibility. Also test your code with different popular devices, since some devices have better cameras than others.