Data privacy

No user images are uploaded from the app running in the browser, including those from files, pasted URLs, and the camera feed. The only user data this website retains are SHA-256 hashes of user-scanned QR code data, along with the associated versions and EC levels. So long as you believe in the pre-image resistance of the SHA-2 family (and Node.js's implementation of SHA-256), it would be virtually impossible to retrieve the original data from the stored hashes.

The purpose of storing hashes of codes is to collect usable data on which sizes of QR codes are most common and which error correction levels are chosen by encoding software. Expect some sort of cool visualization of the data on this website when a sufficient amount has been accumulated. If interested, please contact me (see about page) if you wish to audit the relevant server-side code.