Why Isn't My QR Code Scanning?
Almost always one of four things: here's how to check each one.
A QR code that won't scan is almost never a "broken code" problem: it's one of a small, checkable list of design or print issues. Working through these in order fixes the overwhelming majority of cases.
Contrast
A dark code needs a clearly lighter background: low contrast between the two is the single most common cause of a failed scan.
Size for the distance
A code meant to be scanned from a few feet away (a poster, a billboard) needs to be sized up accordingly: a business-card-sized code doesn't work at that distance.
Logo coverage
A logo embedded in the center is fine; a logo or design element covering too much of the pattern isn't: keep the core pattern mostly unobstructed.
The quiet zone
Leave a real margin of plain background around the code: cropping it too tight interferes with how a scanner locates it.
Frequently asked questions
Questions people actually ask
For small print like a business card or flyer, roughly 2×2cm (0.8×0.8in) is the practical floor: smaller than that and most phone cameras struggle to focus on it cleanly.
It can, if the logo covers too much of the pattern. Kept to a reasonable size in the center, a code's built-in error correction accounts for it and it stays fully scannable.
Test it with more than one device and app: some third-party scanner apps are less capable than a phone's native camera. If it still fails everywhere, regenerate the code rather than continuing to troubleshoot the same image.