LockHTML - Lock any file behind a PIN

LockHTML

Turn any file into a PIN-protected document — optionally viewable only once. Everything happens locally in your browser; nothing is uploaded.

GitHub AES-256-GCMArgon2id100% offline

Drop file(s) here

or click to choose — any file type

…or choose a whole folder

Secret PIN or passphrase

The PIN cannot be recovered — if it is lost, the file cannot be opened.

One-time view Require a keyfile Streaming bundle (large files)

Advanced options

Key derivation

Max views (blank = unlimited)

Do not open before

Expires after

Watermark text (shown over the document)

Recipient public key (X25519, base64) — lock to a person instead of a PIN Split the key (Shamir) — e.g. 5:3 means 5 shares, any 3 open it Duress PIN (opens a harmless decoy page) Hidden volume — a second PIN that opens different content Hidden content (HTML or text file)

Security note: the PIN provides real encryption — without it the file is unreadable even if the source is inspected. "One-time view" is a browser-enforced deterrent, not a server guarantee: a recipient can still copy the file or screenshot the decrypted page.

LockHTML · MIT License · runs on any OS
CLI: pip install lockhtml · lockhtml lock file.html --pin 1234