Introduction
A QR code is a two-dimensional barcode that stores text, a URL or another short payload. A scanner reads the pattern and presents the encoded content to the user.
Most generated QR codes are static: changing the destination requires creating a new code unless an external redirect service is involved.
Key concept
More data produces a denser pattern. Error correction can help a code remain readable when a small part is obscured, but it does not make every damaged or poorly printed code reliable.
Example workflow
Enter a complete HTTPS URL, generate the code and test it from another device before publishing or printing it. Leave a clear quiet zone around the code and maintain strong contrast.
Common mistakes
Very small codes, low contrast, stretched images and decorative overlays can reduce scanning reliability.
Do not encode passwords, private tokens or confidential information. Anyone who can scan the image can read its payload.
Safe scanning habits
Preview the decoded destination before opening it, especially for codes from unknown sources. A QR code can hide a misleading or harmful link just as ordinary text can.