Marketers spend some $20.6 billion a year on mobile ads, according to Trinity Digital Marketing. A big chunk of it is totally wasted, because the QR codes those ads contain can't send interested consumers where they're supposed to.
But more often, it's because, with so many variables – different coding generators, different smartphones, different sizes and scanning distances, to name a few – nobody really knows just how to make sure QR codes are reliably scannable.
Or at least they didn't, until yesterday.
Dr. Kevin Berisso, director of Ohio University's Automatic Information and Data Capture lab, has actually been testing these different variables. And though his work's still in progress, he presented some very useful pointers at yesterday's ProMat 2013 show:
- Know who'll see your QR code. While millions of Americans use smartphones, some use them more than others. Proportionately, about twice as many Millennials, age 18 to 29, own smartphones (66 percent) as their parents' generation (34 percent), age 50 to 64. Urban- and suburbanites outnumber rural residents by a 20-21percent margin. (Signal availability may be a factor here.) People with at least some college education are about twice as likely to own smartphones as people who got no farther than high school. So check Pew's 2012 tracking survey results against your target demographics.
- Know what you want them to do once they see it. Want them to watch a video? Enter a sweepstakes? Find your location? Get product information? Buy something? You need to decide in advance, then set up the landing page accordingly. Otherwise, your brand will suffer from the And Then What? effect – especially if you send consumers to your conventional website (takes forever to open) or anything with Flash (doesn't run on iPhones).
- Make sure they can do it. Three-quarters of the time people scan for product information in retail stores, they can't get it, Berisso notes. This alienates prospective customers much more than never having offered information in the first place.
- Make your links ALL CAPS. That way, you'll have more information in a smaller QR code.
- Choose a lower error correction level. Error correction is the QR code equivalent of autocorrect. The lower the level, the smaller your QR code can be – up to a point. A code with 15 percent error correction is often the same size as one with 7 percent, but it's far less vulnerable to distortion.
- If your code's for a color ad, avoid rich black. Full-color ads are a blend of four different colors – blue (cyan), red (magenta), yellow, and black. Art directors love "rich black," a blend of all four colors. Scanners don't, because if the plates for all four colors don't line up perfectly (this is known as being out of register), it'll fuzz up your QR codes and make them unscannable. Better to confine black QR codes to the black plate. It may not look as pretty to the human eye, but it looks just great to smartphone scanners.
- Choose your generator very, very carefully. Different generating apps give you different quality QR codes. There's proprietary hardware that can check your code and grade it from A through F. A grade of C should be your bare minimum; anything less may work, but you want to be sure your code works well.
- If you simply have to put a logo or product image in your QR code, keep it small. The whole left half of your QR code contains error correction modules. The more you cover them over with logos and such, the more corrupted your QR code can become. Art directors won't have a problem with smaller logos, but clients might.
- Keep the contrast high. That way, scanners can see your QR code better.
- Post the code on a flat surface. Curved surfaces can distort it. That's why the QR code in the photo above is easier on human eyes than scanners.
- Don't get fancy. So-called designer codes, with different orientation, perspective, unsquare squares, or circles instead of squares may look cool, but they won't scan. Codes with reversed colors (i.e., dark background with white cells) will work on some but not all scanners, so why take a chance?
- Size matters. The AIDC lab's testing measured how big a QR code must be to scan from what distance. The key measure here is what's called the X dimension, which is the size of one side of one square inside a QR code, measured in thousandths of an inch. A typical QR code is 25 squares wide by 25 squares high (or 625 square squares). As you might expect, the bigger the QR code, the farther away it can be scanned from. A 3.9" by 3.9" code is scannable from three to six inches away, while a 50" by 50" symbol was scannable from a distance of 17 to almost 70 feet.
- Print medium matters. Magazines, which print at 300 dots per inch, are higher resolution than newspapers, which are 110 dpi or less. So to avoid distortion, you should go bigger in newspapers.
- Type of phone matters. Of the smartphones tested, neither the BlackBerry Curve, the iPhone4 nor a Motoblur could scan QR codes with X dimensions as small as 15.8. The HTC HD7-1, which runs Windows Phone 7, was able to scan 50" by 50" QR codes from the furthest distance – a little over 69 feet.
- Operating system doesn't. In a telephone interview, Berisso told us he was surprised to see that Apple's iOS and Google's Android performed about equally well.
- Don't take anything for granted. Test your QR code on different smart phones with different scanners. That's what Dr. Berisso did. He had 127 smartphone owners (so far) scan 22 different QR codes on 11 different-brand smartphones with 14 different scanners. You don't have to go quite that far, because you're not trying to quantify scientific principles. But you should definitely test your QR codes on different phones and different scanners to make sure they do, in fact, work.