File & Text Encryption
Encrypt and decrypt text or files with a password using AES-256. Everything happens in this browser; your text, files and password are never sent to a server.
Encrypts your text in the browser and makes a "one-time link". The server briefly holds only the ciphertext; the decryption key stays after the # of the link and is never sent. It is deleted from the server the moment the recipient opens it.
Your link
When the recipient presses "Open", the text appears and disappears from the server. It cannot be viewed again, so they should copy it if needed. Pass the whole link, including the part after #.
- Text only (no files), up to 20,000 characters, kept up to 7 days.
- A messenger's link preview opening the address does not delete the note. It is deleted only when the recipient presses "Open".
- Anyone who has the link can open it once. Send it only through a channel you trust. For extra safety, encrypt the text with a password in the Text tab and send that result instead.
- The server does not record who created a note, and you cannot list or delete the links you made.
How it is protected
- AES-256-GCM encryption. GCM also detects changes, so a tampered file or a wrong password makes decryption fail.
- The key is derived from the password with PBKDF2-SHA256 (600,000 rounds). A fresh salt and iv are used every time, so encrypting the same data twice gives different results.
- The file name is stored inside the ciphertext and is not visible from outside. The output file is the original name + .mnc.
- A weak password cannot be rescued by the iteration count. Use a random string of 12+ characters (see the password generator).
- This format (MNC1) is specific to this tool and is not compatible with other programs such as 7-Zip or GPG.
FAQ
What if I forget the password?
It cannot be recovered. Nothing is stored on a server, and the data cannot be decrypted without the password by design.
Can I encrypt large files?
Files are processed whole in memory, so the limit is 100 MB. For bigger files use your archiver's encryption or GPG.
Can I send the result text through a messenger?
Yes. It is plain Base64 (letters and digits) and pastes anywhere. Send the password through a different channel.
How to use this tool
Use it to lock sensitive text or files with a password. It encrypts and decrypts text and files with AES-256 and can create a one-time secret-note link. Text, files and passwords are processed only in this browser and never sent to a server. A lost password cannot be recovered.
Frequently asked questions
How does it encrypt?
It uses AES-256 encryption with your password, for both text and files.
Can I recover a forgotten password?
No. Because your password, text and files never go to a server, nobody — including us — can unlock them. Keep your password safe.
What is a secret-note link?
A way to pass an encrypted note by link. A note that has been opened is deleted on the spot, and one nobody opened is deleted when it expires.
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