Do QR codes expire? The honest answer

Short answer: no, a QR code cannot expire. It is a pattern of squares. It is ink on paper, or pixels in a file. There is no clock inside it, no battery, nothing that phones home to ask permission. A QR code printed in 1998 still scans today.

So why do people keep telling you theirs expired? Because two very different things wear the same name.

What actually expires

A static QR code holds your data directly in the pattern. The URL, the Wi-Fi password, the phone number, physically encoded in those squares. Nobody can switch it off. There is no server involved. It works with the internet down, it works if we go out of business, it works forever. It genuinely cannot expire.

A dynamic QR code holds a short link that redirects. That is what makes it editable and trackable, and it is also the catch: the redirect runs on somebody's server. If that server stops answering, the code is a dead square.

So the code never expires. The redirect can.

The part that makes people angry

Plenty of sites advertise a "free QR code generator", quietly hand you a dynamic code, and start a trial clock. Fourteen days later the redirect stops, or it starts showing an upgrade page instead of your content. Your flyers are printed. Your posters are up. The code in the shop window now advertises somebody's pricing page.

That is not a bug in their product, it is the product. The printed code is the leverage.

I find this genuinely nasty, which is a large part of why qr-cow exists.

How to check what you have got

Scan your own code and look at the raw text before opening it, most phone cameras show it as a preview:

• You see your actual URL, your SSID, your phone number: static. Safe forever.
• You see somebody else's short domain, something like xyz.co/a8Fk2: dynamic. It works exactly as long as they let it.

If it is the second one and you did not knowingly sign up for a redirect service, that is worth knowing before you print another thousand.

What we do

Static codes are free, no account, no trial, no expiry, and they will never be anything else. There is no clock to start because there is no server in the loop. You download a PNG and it is yours.

Dynamic codes cost $3 a month, because a redirect that has to answer every scan for years is a real running cost and pretending otherwise is how you end up with the trial-clock business model. If you stop paying, the redirect stops. We say so up front rather than after your print run.

So which should you print?

If the destination will never change, print static and forget about it. Wi-Fi codes, vCards, phone numbers: static, always. Free, permanent, done.

If the destination might change, or you want to know how many people scanned it, you need a redirect, and you should pick who runs it deliberately. The full comparison is here.

Make one now, static, free, no expiry, no email address.