Utilarc

Encrypt and decrypt text or files with a password

Lock text or any file with a password using AES-256 encryption, and unlock it later. Runs in your browser; nothing is uploaded. Everything runs in your browser; nothing is uploaded.

How to use it

  1. Choose Encrypt, then Text or File.
  2. Enter a strong password. Share it with the recipient through a different channel than the data.
  3. Copy the encrypted text, or send the downloaded .enc file.
  4. To read it, open this page, choose Decrypt, and enter the same password.

How it works

Your password is stretched with PBKDF2-SHA256 (600,000 rounds, random salt) into a 256-bit key. The data is encrypted with AES-256-GCM, which also detects a wrong password or any change to the data. All of this runs in your browser with the built-in Web Crypto API; nothing is sent to a server.

Questions

Can you recover my data if I forget the password?

No. There is no back door and nothing is stored. Without the password the data cannot be decrypted.

Is AES-256 secure?

Yes. AES-256-GCM is used by banks and governments. Security then depends on your password: use 12+ characters or a passphrase of 4–5 random words.

Why is the output different every time?

A new random salt and IV are used for each encryption, so the same text and password never produce the same output. This is expected and safer.

Can other tools decrypt it?

The format is standard (PBKDF2-SHA256 + AES-256-GCM) but the packaging is specific to this tool, so decrypt it here.

More tools