OncePad

Secure one-time secret and file sharing. Share it once, let it fade.

Encrypted in your browser. Opened once, then simply gone.

1 Your secret
2 Your passphrase

Send these on a separate channel from the link — it carries no key, so we can't recover them.

✓ 7 words · very strong

Encrypted in your browser — we store ciphertext we can't read.

How it works

  1. Paste a secret. A password, an API key, a .env block. Your browser encrypts it under a generated 7-word passphrase — end-to-end, before anything leaves the page.
  2. Send two things on two channels. The one-time link carries no key, so it can go in email, Slack, or a ticket; the passphrase goes separately — a text, a call, out loud.
  3. They open it once. The secret is decrypted in their browser and destroyed on the server the moment it is revealed — or after 24 hours if nobody opens it. Nothing is ever written to disk.

OncePad is a free, self-destructing secret sharing service: an encrypted alternative to pasting credentials into chat. Read the full security & threat model.

Frequently asked questions

How does OncePad work?

Your browser encrypts the secret with AES-256-GCM under a generated 7-word passphrase (the key is derived with PBKDF2-HMAC-SHA256, 600,000 iterations) and uploads only the ciphertext. The recipient opens the link, enters the passphrase, and the secret is decrypted in their browser and deleted from the server in the same moment.

Can OncePad read my secret?

No. Encryption happens in your browser and the key is derived from the passphrase, which is never sent to us — the link carries no key at all. The server stores an opaque blob it cannot decrypt, so there is nothing for us, or anyone who breached us, to read.

Why do I get a link and a passphrase?

Two channels. The link carries no key, so it is safe to paste in email, Slack, or a ticket; the passphrase travels separately — a text, a call, said out loud. Someone who sees only one of them has nothing.

What happens after the secret is opened?

It is destroyed on the first reveal — burn after reading, exactly once. If it is never opened it expires after 24 hours. Secrets live only in RAM, never on disk, and a restart wipes them all.

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