How to send a password without it living in a chat forever
A password sent by email or chat sits there for years, waiting for someone else to open the mailbox. A self-destructing link is readable once, and then there is nothing left to leak.
· 3 min read
A colleague needs the login to a shared account. Your parents need the door code. The accountant needs bank access for payments. You do what everyone does: type it into WhatsApp, email or Teams. It works. That is exactly the problem.
A password in a chat never goes away
The message takes a second to send and lives for years. A password sent by email sits in two mailboxes, your Sent and their Inbox, plus both providers' servers and every backup. A chat keeps it in a history anyone can scroll back through years later.
The danger is not today; it is any day after. The recipient's account gets broken into in three years, and the attacker does the first thing attackers do: types "password" into the mailbox search. Everything you ever sent is waiting in one place.
A one-time link: readable exactly once
The fix is the old idea of the disappearing message. The secret is not stored at the recipient's end but halfway, and it is deleted the moment it is read:
- Open Secret message and write what you need to hand over.
- Pick how long the link lives: a day, a week or a month. An unread message deletes itself after that.
- Send the link any way you like, including that same chat.
- The recipient clicks, reads, and by reading destroys it. A second visit only says the message no longer exists.
What remains in the chat history is not a password but a dead link. Whoever finds it in a year finds nothing.
Why we cannot read it either
The obvious objection: fine, the password is not in the chat, but now it sits on your server. It does not, and that is by design.
The message is encrypted right in your browser (AES-256-GCM), and the decryption key goes into the part of the link after the hash sign. That fragment has one very useful property: browsers never send it to any server. What reaches us is ciphertext without a key, unreadable even to us. The key meets the ciphertext only in the recipient's browser.
One more trap we closed: chat and mail apps fetch every link they see to build previews. A naive one-time link would be destroyed by a robot before a human ever opened it. Here, opening the page retrieves nothing; only clicking the button does, and robots do not click buttons.
When to use it
Passwords are the most common case, far from the only one: door and safe codes, guest Wi-Fi credentials, licence keys, ID numbers for a form, card details between partners. The rule is simple: whatever should not sit in a history forever should never enter the history at all.
Frequently asked questions
What if someone intercepts the link?
Whoever holds the link can read the message, just as they could read a password sent directly. The difference: it works once. If an attacker opens it, the intended recipient sees "the message does not exist" and knows immediately that something happened and the secret must be changed. With a password in a chat, you never find out.
Can you see the content of my message?
No. It is encrypted in your browser and the key travels only in the URL fragment, which browsers never send to servers. We store ciphertext we cannot decrypt.
Will a link preview in a chat destroy the message?
No. Opening the page does not retrieve the message; only clicking the reveal button does.
How long does the link live?
Your choice: a day, a week or a month. An unread message deletes itself when the link expires.
Do I need an account?
No. The tool is free and anonymous; the message is tied to nobody, and we do not know who sent it.