Tools

AES encryption and decryption

AES-256-GCM with a passphrase, entirely in your browser.

Runs in your browserHashing and encryption16.4K
Free

Input

0 BFree up to 20.0 KB

Result

The result will appear here.

Encrypt a short piece of text with a passphrase and get one Base64 string you can send through any channel that carries text. The passphrase is stretched with PBKDF2 before it becomes a key, and the salt and nonce travel with the ciphertext, so decrypting later needs nothing but the same passphrase.

How it works

  • AES-256-GCM, which authenticates as well as encrypts — altered ciphertext fails to decrypt rather than producing garbage.
  • The passphrase goes through 210,000 rounds of PBKDF2-SHA-256, the current OWASP guidance.
  • A fresh random salt and nonce per run, so encrypting the same text twice gives different output.

Where your data goes

Nowhere. This tool runs entirely in your browser: the text you paste is processed by the page and is never transmitted to a server or written to a log.

This tool handles keys and credentials, so nothing about a run is saved, not even to your own history.

What it costs

Free up to 20.0 KB per run without an account. Past that, a run costs 2 points and is saved to your history.

Points come from signing up, checking in daily, commenting and completing your profile.

See how points work

Common questions

Why is the output different every time I encrypt the same text?
Because the salt and nonce are random per run, which is required for security. Identical output for identical input would tell an observer that two messages are the same.
I lost the passphrase. Can the text be recovered?
No. There is no recovery path, by design. Nothing about your run is stored here, so there is nothing to recover it from.
Can I decrypt something encrypted by another tool?
Only if it used the same construction and the same layout of salt, nonce and ciphertext. This tool's format is its own; it is meant for round-tripping with itself.

The open-source behind it

This tool is a self-contained implementation. brix/crypto-js (MIT) does the same job as a library — if you need this behaviour inside your own program, start there rather than calling a web page.

brix/crypto-js

Also known as

  • aes encryption online
  • aes 256 gcm
  • encrypt text online
  • decrypt aes
  • text encryption tool