The content of a QR Code cannot be changed once generated. What is sometimes referred to as a Dynamic QR Code, is a QR Code pointing to a static URL that hosts the actual content (e.g. the real URL). The hosted content can be changed after the QR Code has been printed.
After signing in with a Google Account, this site also allows you to generate Dynamic QR Codes (available under My Codes). They can be handled exactly as our normal QR Codes. We automatically create a static URL for you that points to your actual content. We provide simple view tracking for these Codes. You can also enter a Google Analytics Tracking ID for advanced tracking.
This service is offered completely free of charge without any restrictions.