Yes! Once loaded for the first time, your browser caches the app using a Service Worker. After that, you don't need an internet connection to generate or scan QR codes.

Nothing leaves your device. Since this is a static site, all QR code generation and scanning happen entirely locally within your browser. We do not collect, store, or transmit any usage data, analytics, or personal information.

This app relies on two excellent open-source libraries: html5-qrcode for scanning QR codes via your camera or images, and qr-code-styling for generating and customizing the QR codes.

On Android (Chrome), tap the browser's three-dot menu and select "Install App" or "Add to Home Screen". On iOS (Safari), tap the Share icon and select "Add to Home Screen". This lets you use it in full-screen mode like a native app.

PWA stands for Progressive Web App. It is a modern web technology that allows a website to function exactly like a native mobile or desktop app, offering features like offline capabilities, home screen installation, and seamless performance.

Error correction allows a QR code to be partially obscured, damaged, or covered (like adding a center logo) while still remaining scannable. Higher error correction levels (like 'High') make the QR code pattern denser but much more resilient to damage.

If the background and foreground colors are too similar (e.g., light gray on white), older smartphone cameras will fail to read the QR code. Use the built-in checker to aim for a contrast ratio of at least 4.5:1 to ensure scanners can easily read it.

This project is completely open-source and transparent. You can view, audit, or contribute to the source code on GitHub at https://github.com/1bl4z3r/qr.