QR code not scanning?

Most QR codes that fail have one of a handful of problems. Go through these in order. The first four cause most failures.

1. Not enough contrast

Cameras need a dark code on a light background. Pale colors like yellow or light gray, or a busy photo behind the code, make it unreadable. Use a dark color on white.

2. Colors are reversed

A light code on a dark background fails on many phones. Keep the code dark and the background light.

3. Printed too small

As a rule, make the code at least a tenth of the distance people scan from: 2 cm for a business card held in the hand, 10 cm for a poster read from a meter away. Bigger is safer.

4. No margin around it

Leave a clear border around the code, about the width of four of its small squares. Text, frames or the edge of the paper touching the code stop it from scanning.

5. Too much data

A very long link makes a dense code with tiny squares. Use a shorter link, or an editable code, which always stores a short link however long your destination is.

6. Blurry, glossy or curved print

Print from SVG or PDF rather than a small screenshot, which blurs when enlarged. Glare from glossy lamination and codes wrapped around bottles or cups are also hard to read.

7. The link is broken

If the code scans but the page fails, the problem is the destination: a moved page, a typo, or a form or file that is no longer shared publicly.

8. The code was switched off

If it opens a page from the QR company saying the code is inactive, it was a dynamic code tied to a plan or trial that ended. See Do QR codes expire?

9. The phone itself

Hold steady 15 to 30 cm away in good light and wipe the lens. On older Android phones, turn on QR scanning in the camera settings or use Google Lens. iPhones read codes in the Camera app by default.

Test before you print

Scan a printed test copy with two different phones, at the size and distance it will really be used, before printing the full run.