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AES Encrypt / Decrypt

Encrypt or decrypt text with a password using AES-256-GCM. The encryption runs entirely in your browser, the password never leaves the page, and the result is a portable text envelope you can paste into an email, a chat, or a file.

AES Encrypt / Decrypt — Encrypt text with a password and paste the result into an email, a chat, or a file. The recipient decrypts with the same password.

Encryption and decryption run in your browser. The password and the message never leave the page.

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What is aes encrypt / decrypt?

Encrypt text with a password and paste the result into an email, a chat, or a file. The recipient decrypts with the same password.

Encryption is AES-256-GCM (authenticated, so tampering is detected). Keys are derived from the password with PBKDF2-SHA256 and 250,000 iterations. Everything runs in your browser — the password and the message never reach a server.

How to use it

  1. Choose encrypt or decrypt

    Two modes. Same password field, different input and output sides.

  2. Pick a strong password

    A random 20-character string is the right pick for sensitive data. Use the password generator if you do not have one.

  3. Encrypt or decrypt

    The result is a portable text envelope you can paste anywhere.

Examples

Send a one-time secret in an email

Encrypt a password, a token, or a short message with a passphrase. Send the ciphertext in an email, share the passphrase by phone. The recipient pastes the ciphertext, enters the passphrase, and gets the original.

Plaintext: "Meeting at 3pm, use the back door"
Password: "blue-river-42"

Result: A v1:base64... envelope that decrypts only with "blue-river-42".

Encrypt a note for yourself

Store a ciphertext in a note-taking app, a password manager, or a file. Decrypt it from any device with the password. Useful for API keys, recovery codes, or anything you do not want in plaintext.

Plaintext: an API key
Password: a strong password you remember

Result: The ciphertext is safe to store. Only the password unlocks it.

Frequently asked questions

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Last reviewed: 2026-08-17