Static vs Dynamic QR Codes: What Is the Difference?

A code in which the data you entered is the data in the pattern. Scan it and the phone has everything: the URL, the text, the WiFi network name and password, or the contact card. Nothing is looked up from the company that made the code, so there is nothing to expire and nothing to switch off.

The cost is that the content is fixed. If a printed code points at a URL that later changes, the only fixes are to redirect that URL on your own site or to reprint.

A code that contains a short URL belonging to a QR service. When someone scans it, the service's server records the scan and redirects the phone to the destination set in your account. Bitly, which sells them, describes dynamic codes as using "a modifiable short URL to redirect users to your latest landing page", with "editable URLs and automatic tracking".

The pattern itself is not special. A scanner reads a URL either way, and "dynamic" describes the server behind that URL. That has two consequences. The code only works while the redirect exists: Bitly's article notes that on some services' free trials a dynamic code "may expire if you don’t upgrade". And you can build the same thing yourself by encoding a URL on a domain you control and changing where it redirects.

Static only. The generate.now QR code generator encodes exactly the text shown on the page, for a URL, plain text, WiFi details or a vCard. There is no redirect through generate.now and no scan is reported to us, so a code keeps working for as long as its content is valid. It cannot be edited after you print it.

It depends on the version, which is the size of the grid, and on the error-correction level. Versions run from 1 (21 × 21 modules) to 40 (177 × 177). Error correction lets a damaged code still scan: level L restores about 7% of the code, M about 15%, Q about 25% and H about 30%. A higher level leaves less room for data.

A longer URL needs a larger grid. Printed at the same physical size, a larger grid means smaller modules, which are harder for a camera to resolve. This is the practical argument for a short link, whether it comes from a dynamic-code service or from your own domain.

Use a static code when the content will not change and you do not want the code to depend on anyone's service: WiFi details, a contact card, a link to a page you control. It costs nothing to keep alive.

Use a dynamic code when the destination may change after printing or you need scan counts, for example on packaging or a long-running campaign. If you do, check what happens to the code when the subscription ends, or run the redirect on your own domain so the printed code never depends on a vendor.