How QR Codes Go Wrong
QR codes are everywhere these days, from restaurant menus to real-estate flyers. They are very convenient - until you come across one that refuses to be scanned.
We are going to explain how they work, how they don't work, and how you can use them for your own work.
What are QR codes?
Due to covid distancing, we gotten used to scanning the QR codes. Thezd are 2D codes that look like this:
When scanned with a smartphone or QR code reader, the encoded data is quickly retrieved, whether it's a website URL, a video, or something different.
They have became so ubiquitous, that QR-scanning phone apps have been replaced by our inbuilt camera apps, which now recognize and link to QR codes as you use them. So the process is clear to use these days - we can view a QR code with our camera, a link is generated inside our app, and we click on the link.
So we know how we use these QR codes - how do they work at a deeper level?
QR codes, short for Quick Response codes, are two-dimensional barcodes that store information. So in order to understand QR codes, let's quickly detail how barcodes work.
Barcode Detour
We've all seen Barcodes and scanned them at self-checkout - they're patterns of lines that represent typically represent numbers.
The width and order of the lines form a special code that computers (like a checkout kiosk) can read almost instantly. Think of it like Morse code but with thick and thin lines instead of dots and dashes.
See a simple example where I use a barcode to represent a series of 1s:
There is a lot to mention here, but I'll just focus on two things
- The bar patterns on the left don't match the bar patterns on the right, even though we are using 1s throughout
- There is a weird 7 on the right
The reason that the 11111 has different bars from the right, is to make it easier for scanners to detect direction. A scanner shines a laser on the barcode, and measures how much light bounces back. Black bars absorb light (low reflection), and white spaces reflect it (high reflection). By detecting these patterns of light and dark, the scanner can turn them into digital information.
The 7 is more interesting. It's the result of a calculation based off of the other numbers, and is referred to as a checksum. Essentially this number sanity-checks the other numbers to confirm that they haven't been smudged or damaged. Otherwise you could accidentally be scanning a much more expensive item!
How does this relate to QR Codes?
QR Codes are a more complicated version of these barcodes, but in 2 dimensions. Even though the previous barcode looks like it's 2D, it encodes a single dimension worth of data (a thelong single number that the bars represents).
With a QR code's dimensionality, it can encode far more data - up to 3 kilobytes. By contrast, a UPC code "only" encodes billions of numbers so we can conceivably exhaust the supply.
How do QR codes break?
Despite their convenience, QR codes can fail to deliver the intended user experience. One common reason is poor placement – if a QR code is placed in a location with poor lighting or at an awkward angle, scanning becomes difficult. Additionally, low-quality printing or placing the code on a reflective surface - say a screen behind a window - can hinder scanning.
One of the most common pitfalls is linking to a non-mobile-friendly website, or even an abandoned one.
Another issue is using overly complex QR codes with too much data, causing scanning errors. Cute QR codes, embedding images or branding, are particularly prone to breaking.
How can you use them most effectively
To ensure the success of your QR code campaign, follow these best practices: use high-quality printing to ensure clarity, test the code in various lighting conditions, and always link to mobile-optimized content. Keep the design simple and ensure the code is large enough to scan easily.
By understanding how QR codes work and the common pitfalls to avoid, you can create successful campaigns that engage users and drive results. Remember, the key to a successful QR code is a smooth path from scan to content delivery.
And if you've made it this far, your reward is this fun video, showing you how to build a qr code with your bare hands: