Text Encryption (AES)

Encrypt and decrypt text with a password using AES-256, right in your browser

0 characters
Use a long passphrase: four or five unrelated words are strong and easy to say over the phone.

Runs entirely in your browser. Nothing you type or upload is sent to us or stored. How we handle privacy

Encrypted text
Type your text and a password, then tap Encrypt.
There is no password reset. If the password is lost, the text can't be recovered by anyone, including us.

Runs entirely in your browser. Nothing you type or upload is sent to us or stored.

Results are for general guidance. Please check anything important before relying on it. Terms of use

How to Use

  1. Choose Encrypt, then type or paste the text you want to protect.
  2. Choose a password and type it again in the second box (or tap the eye icon to see it instead). A few unrelated words make a strong password that's easy to say over the phone.
  3. Tap Encrypt (or press Ctrl+Enter in the text box). After a moment you get a block of text starting with DT1.. Tap Copy or Download .txt.
  4. Send the encrypted text by WhatsApp or email, and tell the other person the password some other way, such as a phone call.
  5. To read it, choose Decrypt, paste the whole DT1. text, enter the password and tap Decrypt.

Encrypt text with a password

This text encryption tool locks a message with a password using AES, the same cipher banks and governments use. Only someone with the password can read it. It's useful when you need to send something private over a channel you don't fully trust: a locker number to a family member, Wi-Fi details to a tenant, account details to your CA, or notes you keep in a cloud drive. Encryption and decryption both happen in your browser. The text and the password are never sent to us or anyone else, and nothing is saved.

How it works

A password on its own isn't a good encryption key, so the tool first stretches it into a 256-bit key with PBKDF2, running SHA-256 310,000 times. That makes each password guess slow for an attacker. It then encrypts the text with AES-256 in GCM mode, which also adds a check value, so any change to the encrypted text is detected.

key = PBKDF2-SHA256(password, salt, 310,000 rounds) โ†’ 256 bits
ciphertext = AES-256-GCM(key, iv, text)
output = "DT1." + Base64(salt 16 bytes | iv 12 bytes | ciphertext + 16-byte tag)

The salt and IV are random and new every time. Encrypt the same message twice with the same password and you get two completely different results; both decrypt to the same text. The "DT1." at the start marks the format, so the tool can tell its own output from other text.

OWASP's password storage guidance used 310,000 PBKDF2-SHA256 rounds in 2021 and has since raised its suggestion to 600,000. The bigger factor by far is the password itself, as the table shows.

How strong should the password be?

PasswordExampleVerdict
A name and a yearPriya1998Weak: tried early by guessing tools
8 random charactersk7#Qm2!xFair for casual use
12 or more random characterst8#Lq!vZ2m@RStrong
4 or 5 random wordsmango river tiffin windowStrong, and easy to say on a call

Sharing encrypted text

The encrypted block is plain text, so you can paste it into WhatsApp, Telegram, email or SMS, or save it as a .txt file. If the app breaks it over several lines, that's fine: the tool ignores line breaks and spaces when you decrypt. What matters is that you send the password a different way. If both travel in the same chat, anyone who reads that chat can open the message.

Things to know before you rely on it

  • There is no password reset. If you forget the password, nobody can recover the text, including us. Keep the password somewhere safe.
  • When decryption fails, the message says "wrong password, or the text was changed". AES-GCM can't tell those two apart, which is exactly why it is safe. Check capital letters first, then make sure you copied the whole block.
  • This is for text. To protect files or PDFs, use a tool made for that.
  • The format is open: any program that follows the steps above can decrypt it, so you aren't tied to this website.

Frequently Asked Questions

No. The password never leaves your browser and we don't keep a copy of anything, so there is no reset. Without the exact password the text is gone for good.

Yes. AES-256 is the standard used by banks and governments, and no practical attack on it is known. The weak point is the password: use a long one, and don't send it in the same message as the encrypted text.

Usually a small difference: a capital letter, a space at the end, or a part of the encrypted text missing. Copy the whole block again, from DT1. to the last character, and type the password carefully.

Yes. It is plain text, so WhatsApp, email and SMS all work, and line breaks added by apps don't matter. Share the password separately, for example on a phone call.

No. Encryption and decryption run in your browser with the Web Crypto API. Nothing you type is sent to us or stored.