On my way home from work I go by a particular billboard that has caught my eye for the past few weeks. It’s not the headline or some crazy photo – it’s that it has a QR code. To be specific, the billboard’s main image is a belt buckle with a QR code right in the center. It’s a neat idea, something you don’t see every day, and attention-getting for sure. The problem? It’s not properly executed. The code is completely un–scannable (not to mention even attempting to scan it is incredibly dangerous unless you are a passenger.) The code is simply too small for the distance away a person would be when scanning it, not to mention the speed at which they are traveling.

It seems this company didn’t realize the QR code wouldn’t work in this application. But usability is key with mobile marketing – if you’re going to take the leap into this arena, it must be properly executed. After all, you went through all the time to create an entire mobile strategy (at least, hopefully you did). You built a shiny new mobile version of your website, added some videos to your YouTube page and created the 2-dimensional barcodes to get mobile visitors there. Maybe your even in the process of building an app. You’re ready put them on some ads, literature, direct mails, basically every marketing piece you have. That’s all there is to it right? Not quite. Let’s say you also want to target it to a more non-traditional avenue to make a bigger impact, like some large-scale signage. But to be sure it’s not a wasted effort, some careful planning – and a little bit of math – is involved.

The size of the code is something easily overlooked, especially if you are used to putting them on pieces that will be inches from the viewer. Unfortunately there seems to be no exact rule on code size, as each phone’s camera lens and resolution play a major role in how easily the code is scanned. There is however a general rule of thumb. The ratio should be around 10:1, so a 1 inch code should be successfully scanned by most phones 10 inches away. Let’s translate this to the billboard. If I estimate that six lanes and the ditches between me and the billboard equal 100 feet, that code should be a massive 10 feet tall. With a standard interstate billboard size of 14 feet high, the code would have to be almost as tall as the billboard. And this equation doesn’t even take into account speed traveled, which can vary based on the location, time of day and other outside factors affecting traffic flow.

The bottom line: It’s great to try new and different things, but don’t forget to put in the time to test and research if it will even work. Otherwise, you may frustrate your audience – and no one will ever have the chance to see that great, new mobile site you took so much time to create.

Have you seen codes or tags on a billboard? Where are some other unique places you’ve seen them? And most importantly, were they properly executed?