How the check works
Once a day we request each active code’s destination:
- with a 10-second timeout and up to 5 redirects;
- never to private or internal network addresses;
- alternating between our own user agent,
StandfastQR-LinkCheck/1, and a mainstream mobile browser’s, so pages can’t show the checker something different from scanners.
What counts as healthy or failing
| Result | Counts as |
|---|---|
| 2xx or 3xx | Healthy |
| 401, 403, 429 | Unknown (not broken) |
| 404, 410, 5xx, DNS failure, TLS failure, timeout | Failing |
What happens after three failing days
- We safety-check your fallback address again.
- The code switches to fallback.
- Scanners go to your fallback URL, or, if you haven’t set one, to a simple StandfastQR page saying the page is temporarily unavailable, with your optional message.
- We email you.
After two healthy checks in a row, the code switches back to your destination automatically and we email you again.
Setting a fallback
Open a code and set a fallback URL (for example your homepage) and an optional short message, such as “Our menu is being updated. Call us on …”.