QR code not scanning? 9 fixes that work
A QR code that won’t scan is frustrating but almost always fixable. Work through these nine causes in order — most problems are one of the first three.
1. Low contrast
Scanners need a clear difference between the dark modules and the light background. Dark-on-light works best. Avoid light codes on dark backgrounds, and never use two similar tones.
2. Too small for the distance
Follow the 10:1 rule: a code should be about one-tenth of the distance it’s scanned from. A code on a poster read from 3 metres needs to be roughly 30 cm wide.
3. No quiet zone
The code needs a clear margin (about four modules) around it. Text or graphics crowding the edges confuse the scanner. Give it breathing room.
4. Blurry or low-resolution print
A code exported as a small raster image and then blown up becomes fuzzy. Export a vector SVG or PDF so it stays sharp at any size.
5. Inverted colours
Some scanners struggle when the code is lighter than its background (a “negative” code). If yours won’t read, switch to dark modules on a light background.
6. Logo too large
A centre logo that covers more than about 30% of the code destroys too much data. Shrink the logo and set error correction to High.
7. Damaged or distorted surface
Codes on wrinkled, curved or reflective surfaces can fail. Print on a flat, matte surface and avoid lamination glare.
8. The destination is broken
Sometimes the code scans fine but the link is dead. Test the destination URL in a browser. With a static code you’ll need a new code if the link changed.
9. Test before you print
Always scan the final artwork with more than one phone before a print run. Our built-in scan-safety meter flags contrast, logo size and data-length problems before you download.
Frequently asked questions
Why does my QR code scan on one phone but not another?
Usually marginal contrast, size or a slightly oversized logo — it works on a good camera but fails on a weaker one. Increase contrast and size, and reduce the logo.
Can a QR code be too complex to scan?
Yes. Very long data creates a dense code with tiny modules that are hard to read at small sizes. Shorten the URL or increase the printed size.
Does printing in colour cause scanning problems?
It can, if contrast is low. Keep the dark modules genuinely dark against a light background and test before printing.
Build a reliable, tested QR code free.