Dynamic QR codes: the complete guide
This guide is about link QR codes: menus, catalogs, posters and campaigns. It is not about payment QR codes, which work through a different mechanism and are generated by your bank.
A dynamic QR code is a code whose image never changes, but whose destination you can swap after printing. It manages that because it does not store the final address: it stores an intermediate address, resolved at the moment someone points a camera at it.
What the difference between dynamic and static is
| Static | Dynamic | |
|---|---|---|
| What the code stores | The final address, baked into the image | An intermediate address |
| Changing the destination after printing | Impossible | Yes, as often as you want |
| Scan counting | Does not exist | Yes, per code |
| Depends on a service staying online | No | Yes |
| Image density | Higher, with long URLs | Lower, easier to read |
Static codes have a real advantage: they work forever, depending on nobody. If the content will never change and you do not want to depend on a service, static is the right call.
Dynamic codes are for when the destination may change, when you want to measure, or when the printed material will outlive the campaign.
Whether free dynamic QR codes expire
It depends on the service, and this is where most people get burned. Many free generators:
- Expire the code after a few days or a number of scans
- Limit how many dynamic codes an account can hold
- Start showing an interstitial page with ads
- Switch the code off if you do not subscribe after the trial
The question to ask before printing is always the same: what happens to this code if I stop paying? If the answer is "it stops working", do not print ten thousand of them.
On I LOVE HTML, QR codes are in every plan, including the free one, within that plan's file limit. The code keeps resolving as long as the file is active.
Why create several codes for the same page
Because the image is identical for the reader, but the count is separate for you. One code per store, per city or per magazine answers which physical spot actually brings people in, and that answer does not exist when every poster carries the same code.
The detail almost nobody measures: scans and views are different things. The scan happens at the moment of the scan; the view happens when the page opens. Many scans with few views means the poster works and the page does not. Services that only redirect lose the visitor in that gap and cannot count both ends.
Customisation, verification before download and the print sheet are covered in The QR code that changes destination after printing.
The mistake that kills most QR codes in the street
Size and contrast. A code printed too small for the reading distance does not work, and a light code on a light background does not either. The rule of thumb is simple: the further away the reader stands, the bigger the code needs to be.
It is worth checking whether your generator tests the code before releasing the download. Many do not, and the problem only shows up after the print run.
When a QR code is not the answer: if your audience is already in front of a screen, a clickable link converts better. QR codes solve the jump from the physical world to the digital one, not the other way around.