Shared secret creation

My public key:
Their public key:
Shared secret:

Instructions

1. A random My public key is generated every time this page is refreshed. It is read-only and base64 encoded.
2. Send this key to another party which has their own instance of this page.
3. Get their public key from them.
4. Do not refresh this page while the public keys are being exchanged.
5. Paste their public key into the designated field. The Shared secret will appear if the key is valid.
6. The other party must do the same on their end to view the Shared secret.

The Shared secret can be used as a password to encrypt and decrypt a private message between you and the other party. For example, zip files (7zip is preferred) can be password encrypted and sent as email attachments. [Tip: send an encrypted message containing a shorter password for future use.] Short text messages can be encrypted/decrypted with the Shared secret above using the boxes below.

Encryption

Message to encrypt/decrypt:

Instructions

1. Create a Shared secret at the top of this page.
2. Type or paste text into the Message box and click on the Encrypt/decrypt button. The encrypted message appears in the Message box in place of the original message.
3. Copy the encrypted message and send it to the other party. When they receive it, they can paste it into their own Message box
4. If they have the Shared secret, they can decrypt the message by clicking on the Encrypt/decrypt button. The original message will appear in their Message box in place of the encrypted message.
5. They can reply to your message by following these instructions on their end.

Source code and security notes