Almost every unscannable QR code fails for one of a few repeat reasons. Work through this checklist top to bottom.
1. Colors too light or inverted
A QR code must be dark modules on a light background. Pale yellow or light blue on white — and white codes on black — routinely fail.
2. Printed too small
Rule of thumb: scanning distance ÷ 10 = minimum size. For scanning at 30 cm, the code needs to be at least 3 cm wide.
3. No white margin around the code
QR codes need a quiet zone — empty space at least 4 modules wide on every side. Placed flush against artwork or a page edge, cameras can't isolate the code.
4. Logo too large
A center logo shouldn't exceed 20–25% of the code's width, and you should pair it with error correction level H.
5. Too much data
The more data, the denser the pattern. Very long URLs produce codes so fine that older phone cameras give up. Trim unnecessary tracking parameters from the link.
6. Glossy or curved surfaces
Shiny plastic, glass, or curved cups distort the image. Choose matte printing and flat placement.
7. The file got compressed to mush
QR images forwarded through chat apps get recompressed until the edges blur. Go back to the original file — or download an SVG, which stays sharp at any size.
Still stuck after all seven? Regenerate the code with the default settings, which are tuned for maximum scanability.