Most explanations of QR code expiration say "your subscription expired" as if that's the full story. It's not. QR codes don't expire — the redirect infrastructure that dynamic codes depend on gets switched off, and every scan after that moment hits a dead server instead of your content. Here's how it works at the architecture level, and why it matters if you're building anything that touches physical print. Static vs dynamic: two completely different architectures A static QR code encodes your destination URL directly into the pixel pattern using the ISO/IEC 18004 standard. No server, no lookup, no dependency. Scan it and the camera decodes the URL from the image itself. It will keep working as long as the physical print is readable and the destination URL is live. A dynamic QR code encodes a short URL owned by the QR platform — something like qrtg.io/abc123 . The camera sends an HTTP GET to that short URL.…