AES Encrypt & Decrypt
Encrypt or decrypt text with AES-GCM and a password, entirely in your browser. PBKDF2 key derivation, Base64 output, nothing uploaded.
About the AES Encrypt & Decrypt
This AES tool encrypts and decrypts text using AES-256-GCM, the authenticated encryption standard trusted for TLS, disk encryption and password managers. Type a message and a password: the tool derives a strong key from your password with PBKDF2 (100,000 SHA-256 iterations and a random salt), encrypts with a fresh random IV, and returns a single Base64 blob you can paste anywhere.
Decryption reverses the process — paste the Base64 output back with the same password and the original text appears. Because GCM is authenticated, a wrong password or a tampered ciphertext fails cleanly with an error instead of returning garbage, so you always know whether the message is intact.
Everything runs locally with the Web Crypto API. Your password, plaintext and ciphertext never leave the browser, making this safe for notes, credentials and small secrets you need to send over an untrusted channel.
How to Use the AES Encrypt & Decrypt
- 1Choose Encrypt or Decrypt.
- 2Enter your text and a password (share the password separately from the ciphertext).
- 3Click the button to get the Base64 ciphertext or the recovered plaintext.
- 4Copy the result — decryption needs the exact same password.
Frequently Asked Questions
What encryption does this tool use?
AES-256 in GCM (Galois/Counter Mode), an authenticated cipher. The key is derived from your password using PBKDF2 with 100,000 iterations of HMAC-SHA-256 and a random 16-byte salt. A random 12-byte IV is generated per message, and the salt and IV are stored alongside the ciphertext so decryption can reproduce the key.
Is it safe to encrypt sensitive text here?
The cryptography runs entirely in your browser via the Web Crypto API — nothing is transmitted or stored on a server. The main risk is your password: AES is only as strong as the passphrase protecting it, so use a long, unique one and share it through a different channel than the ciphertext.
Why does decryption fail with the wrong password?
GCM verifies an authentication tag during decryption. If the password is wrong or a single character of the ciphertext was altered, the tag check fails and the tool reports an error rather than returning corrupted text. This is a security feature — it guarantees the message hasn't been tampered with.
Can I decrypt this output in another language or library?
Yes, if you replicate the format: Base64 of salt (16 bytes) + IV (12 bytes) + AES-GCM ciphertext-with-tag, deriving the key with PBKDF2-SHA256, 100k iterations. Any standard crypto library (Python cryptography, Node crypto, OpenSSL) can interoperate once you match those parameters.
Is AES-GCM better than AES-CBC?
For most uses, yes. GCM provides both confidentiality and integrity in one pass, so it detects tampering automatically. CBC only encrypts and needs a separate HMAC to be safe. This tool uses GCM so you get authenticated encryption by default.