QR code not scanning? Work down this list

Scanning failures have a short list of causes. Work top to bottom — the first four cover 90% of cases.

1. Low contrast

Scanners need a dark pattern on a light background. Pastel-on-white, gold-on-cream and grey-on-grey all fail. Our generator warns live when your colour pair is risky — darken the pattern or lighten the background.

2. Inverted colours

White pattern on black looks sharp and breaks many readers — the spec expects dark-on-light. If your design is dark, put the code in a white rounded panel. (We flag inversion automatically.)

3. Printed too small

The distance ÷ 10 rule: a poster code read from 2m must be 20cm wide. In-hand codes under 2cm start failing on older cameras, especially with dense data inside.

4. Quiet zone trimmed

The white border is structural — scanners use it to find the code. Cropped tight against artwork, the code often won't register at all. Restore four modules of clear space.

5. Blurry print or upscaled image

A screenshot enlarged for print smears module edges. Always export fresh at print resolution — SVG or 4096px PNG, both free here.

6. Glare, curvature and placement

Gloss lamination under spotlights, codes wrapped around mugs or bottle shoulders, vinyl over van door ridges — geometry defeats scanners. Flat placement, matte finish.

7. Too much data

A 500-character URL makes a dense 57×57 grid whose modules are tiny at print size. Shorten the link, or use an editable short-link code — 7 characters, maximum sparseness, same destination.

8. The code scans — the link is dead

Half of "broken codes" are working codes pointing at moved pages. Static codes cannot be repointed; that menu PDF you replaced has a new URL and every printed code is orphaned. This is the exact problem editable codes (£10 once) exist to solve.

Still stuck?

Test with our free online scanner — upload a photo of the printed code and see exactly what (if anything) it decodes to.