Why did my QR code stop working?
A QR code that used to work stops for six reasons: the destination moved and the code is static, the link was turned off, the code is too small for where it ended up, a reprint cropped the quiet zone, the surface or light changed, or the destination itself is broken. Work down the list and stop when one fits.
- 1The destination moved and the code is static
Scan it and read the URL your phone shows. If it shows your own web address rather than a klipqr.com link, the code is static — the destination is inside the pattern and cannot be changed. The page it points at has moved or been deleted. Restore the old URL, or reprint with a dynamic code.
- 2The link was turned off
Scan it and see whether you get a page saying the code was turned off. That page means the link exists and someone disabled it — usually a teammate tidying up, occasionally us if a link was reported. Re-enable it from the dashboard and it starts resolving again within about half a minute.
- 3The code is too small for where it ended up
Measure the printed code and divide the scanning distance by ten. A code that worked on a table tent will fail on a wall behind the counter, because the distance changed and the size did not. If the printed width is under a tenth of the distance people stand at, that is the whole problem.
- 4The quiet zone was cropped in a later reprint
Look for white space all around the pattern, about four modules wide. Reprints get re-laid-out, and the blank margin is the first thing a designer trims to make something fit. Scanners use that margin to find the code at all, so cropping it turns a working code into an undetectable one.
- 5The surface or the light changed
Try scanning it in different light, and at an angle. Gloss lamination reflects overhead light straight back into the lens. A code moved onto a bottle, a cup or a curved sign is no longer flat. Same file, same size, different physics.
- 6The destination itself is broken
Open the destination in a browser without scanning anything. If the camera decodes fine and the page errors, the code is working perfectly and the site behind it is not. On a dynamic code this is a thirty-second fix: point the link somewhere that works, and every printed copy follows.
Questions
The things people ask before they commit something to paper.
How long does it take for a change to reach a printed code?
About half a minute worldwide. Re-pointing a link updates the cache at the location nearest each scanner, and the platform holds a cached value for a minimum of 30 seconds, so that is the honest window rather than instant.
My code works on my phone but not on my customer’s. Why?
Your phone is newer, closer, or in better light, so it decodes a code that is borderline. Scanner tolerance varies enormously. Test on an old Android handset in poor light before printing — that is the device that decides whether a campaign works.
Can someone else’s code stop mine from working?
No. Each code resolves independently, and nothing about another workspace’s links affects yours. If several of your own codes stopped at once, look at what they share — a destination domain, a print run, or a reprint that re-laid them all out.