Print a secret on paper that nobody can read. Your words are scrambled with your password first, and only the scrambled text goes into the QR code — the password is never in the code. Anyone can scan the paper; only the password opens it. Same scramble as crypt.oc — blobs open on either site.
Honest limits: one code holds up to 600 characters of secret — longer won't fit a single QR, and cramming more would make a code too dense to scan reliably. Print it big and keep the paper flat and clean; a torn or faded code may not scan, so keep the blob text as a backup if the secret matters. If you forget the password, the secret is gone — nobody can recover it, including us.
Got a blob? Paste it here — from a Paper QR backup, from crypt.oc, or typed in. (This panel reads the blob text. Point-a-camera scanning isn't built in — typing/pasting the blob is the reliable route, so that's what's shipped.)