End-to-end encryption: your data is encrypted in your browser before it ever leaves the device. The operator stores ciphertext only and cannot read your messages or files. Here is everything else.

Cookies used

• clip_token_<id> — An HMAC-signed write token bound to this session ID. Issued by the server after a successful E2EE handshake. Contains no key material — losing it just means re-authenticating. httponly, secure, samesite strict, lifetime tracks the session (max 2h, sliding).
• clip_lang — Language preference. samesite lax, 1-year lifetime. No sensitive data.

Where your key lives

Your AES-256 key is derived in the browser via Argon2id from the password you type and the session ID. The raw key is held in sessionStorage for the lifetime of the browser tab — closing the tab clears it. The key is never sent to the server in any form.

What's stored, what's anonymous

Text and files travel as AES-256-GCM ciphertext encrypted in your browser. The server stores opaque blobs and metadata it cannot decrypt. Filenames and thumbnails are also encrypted client-side. In transit: HTTPS only.

No IP address is logged or stored. Anti-abuse uses proof-of-work (your browser computes a small hash puzzle on each new session and each login attempt) plus per-token quotas. The server cannot link two sessions to the same visitor.

Limits & responsibilities

• The operator runs the server but cannot decrypt your data. The only thing leaving your browser is ciphertext + opaque metadata (size, timestamps). The operator's job: serve the unmodified JavaScript so the crypto runs as documented. If the served code were swapped for a malicious version, that version could exfiltrate your password. This is the inherent trust of any web-delivered crypto — review the source if it matters.
• Anything with code-execution access to the open tab can read the key from sessionStorage — devtools, malicious extensions, malware. Closing the tab clears the key. Your job: keep the device clean and close the tab when done.
• The session URL alone is not enough to read protected sessions — the password is also needed to derive the key. For sessions without a password, the URL is the only secret. Share it through a channel you trust.

Password loss = data loss

With end-to-end encryption, the server cannot reset or recover anything. If you forget the password, the data is gone. Use a real password manager if it matters.

Extra hygiene (optional)

For maximum protection against browser extensions or shared devices, open the session in a private/incognito window. The key in sessionStorage is then scoped to that window only — closing it leaves no local trace. You can also install this site as an app (from the browser's URL bar): the static crypto bundle then runs from your local cache and pins the version you installed.

What we do not do

No tracking, no analytics, no third-party scripts. No content logging. No IP logging. No backup beyond Redis and the ephemeral disk used for in-flight ciphertext. No data sent to any third party. No advertising cookies.

Retention

2-hour sliding window after the last write. After that, everything (encrypted content in Redis and on disk) is automatically deleted. You can also wipe immediately via the "Wipe session" button.