AES encrypt & decrypt — password-based, on-device
Encrypt or decrypt text with a password using AES-256-GCM. It runs entirely in your browser using Web Crypto (0 uploads, works offline), so neither your text nor your password ever leaves your device.
How to use it
- Choose Encrypt or Decrypt and enter a password.
- Paste your plaintext (or the encrypted base64).
- Copy or Download the result.
FAQ
How do I encrypt text with a password for free?
Choose Encrypt, enter a password and paste your text. This page derives a key from your password with PBKDF2 and encrypts with AES-256-GCM, returning a base64 blob that bundles the salt and nonce — on your device with no upload.
Is my text or password sent anywhere?
No. Everything happens in your browser using Web Crypto and nothing is transmitted or stored, which you can verify by turning off your Wi-Fi. Encrypting on a server would mean trusting it with your plaintext.
What algorithm and key derivation are used?
AES-256-GCM for encryption, with the key derived from your password using PBKDF2 (SHA-256, 150,000 iterations) and a random salt per message.
What happens if I lose the password?
There is no recovery. The password is the only key; without it the ciphertext cannot be decrypted, by design.
Limits
Encrypts text with a password; it is not a file encryptor or a key-management system, and a weak password weakens everything.
Related
The password strength auditor checks your password first; the RSA key generator creates asymmetric keys.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.