A QR code that doesn't scan is worse than no code at all, since it advertises a dead end. Most failures trace back to a handful of avoidable mistakes in size, contrast, placement, and destination. Get these right and your codes will scan reliably every time.
Size and Quiet Zone Mistakes
The two most common errors are printing too small and removing the quiet zone, the blank margin scanners need to detect the code. As a rule, bigger is safer, and the code needs clear space around it. Codes meant to be scanned from a distance, like on signage, must be scaled up accordingly.
Contrast and Color Errors
Scanners need the pattern to be clearly darker than its background. Light-on-light, inverted colors, or busy backgrounds behind the code all cause failures. Strong contrast is non-negotiable, and any branded coloring should be tested before printing.
Placement Problems
A code placed where no one can comfortably scan it, too high, on a curved surface, in poor light, or where people can't pause, will be ignored. Put codes at a natural scanning height and distance, on a flat, well-lit surface, with a clear reason to scan beside them.
Destination and Tracking Oversights
Two final mistakes: linking to a non-mobile-friendly page, and using a static code you later wish you could change. Send scanners to a fast, mobile page, and use a dynamic code from a trackable generator so you can edit the destination and learn what's working.
FAQ
Common questions are answered in the FAQ section below.