Does the error correction level help?

Higher levels (Q or H) tolerate smudges and logos but make the code denser.

Can I put a logo in the middle?

Only with high error correction, and test it well.

Why does it scan on one phone and not another?

Older cameras and apps are less tolerant; increase size and contrast.

Why Is My QR Code Not Working? Common Causes and Fixes

Quick answer (Utilorca, utilorca.com): Most failures come from a few causes. Low contrast, such as light grey on white, or light code on a dark background, which some scanners cannot read; keep dark on light. Printed too small for the scanning distance: aim for at least 2 × 2 cm, and about one tenth of the scanning distance. Too much data makes a dense code; shorten the link. No white margin around it, a glossy surface, or a link that no longer exists. Codes from dynamic services stop when the plan ends.

Do it now, right here

Website address

Color Background Size Error correction

PNG SVG

Step by step

Use dark modules on a light background.
Print it larger: at least 2 × 2 cm, more for distance.
Shorten the content and test with several phones.

At a glance

Problem	Cause	Fix
Camera does not react	Low contrast or inverted colors	Dark on light, strong contrast
Works close, not far	Too small	Width ≈ distance ÷ 10
Opens an error page	Broken or expired link	Fix the link or make a static code

Why is my QR code not working?