Encrypt a Message
Encrypt text with a password โ AES-GCM, all in your browser.
Encrypting a message
Type a message and a passphrase; out comes a compact blob starting pikkit1.
that you can paste into any channel โ email, chat, a sticky note. The recipient pastes it
into the decrypt tab with the same passphrase and reads the original. Wrong passphrase, or a
blob altered by so much as a character, fails outright rather than producing garbage โ
that is GCM's authentication at work.
Under the hood: AES-256-GCM, key derived by PBKDF2 (310,000 rounds of SHA-256) with a random salt, fresh random IV per message, all via the Web Crypto API in this tab. Nothing is transmitted or stored.
Using it without undermining it
The scheme is as strong as the passphrase, so use a real one โ the password generator obliges, and the strength checker will audit a candidate. Send the passphrase over a different channel than the message: blob by email, passphrase by phone. And there is no recovery โ a forgotten passphrase is a lost message, by design.
Scope honestly stated: this is for the occasional secret crossing an untrusted channel โ a password to a colleague, notes that shouldn't sit readable in a chat log. For ongoing sensitive communication, a proper end-to-end messenger (Signal and peers) handles key exchange, forward secrecy and metadata far better than any paste-a-blob scheme can. Files rather than text: the file encryptor uses the same construction, and the crypto guide maps when to hash, encrypt or merely encode.
Frequently asked questions
How secure is this encryption?
AES-256-GCM with a PBKDF2-derived key is the current standard for password-based encryption. The practical weak point is always the passphrase โ make it long and share it over a different channel.
Can the message be recovered without the passphrase?
No. There is no back door and nothing stored server-side โ a forgotten passphrase means the message is permanently unreadable. That is the point.
Why does decryption say the message was altered?
GCM authenticates as it decrypts: a wrong passphrase or any tampering with the blob fails verification. Check the passphrase and that the full blob was copied.
Is this as good as Signal or WhatsApp?
Different job. Those handle key exchange, forward secrecy and metadata for ongoing conversations. This is for the occasional secret over channels you don't control.