AES Encrypt / Decrypt
Encrypt and decrypt text using AES-256-GCM with a passphrase. Powered by the browser's native Web Crypto API — nothing is sent to any server.
Output appears here
What is AES-GCM encryption?
AES-GCM (Advanced Encryption Standard with Galois/Counter Mode) is a symmetric authenticated encryption algorithm. It is the gold standard for modern encryption — providing both confidentiality (nobody can read the data without the key) and integrity (any tampering is detected). AES-256-GCM uses a 256-bit key derived from your passphrase via PBKDF2.
How this tool encrypts your data
Your passphrase is never used directly as the key. Instead, PBKDF2 with SHA-256 and a random salt derives a 256-bit AES key. A random 96-bit IV (initialization vector) is generated per encryption. The salt, IV, and ciphertext are all included in the output so decryption only requires the same passphrase.
Is this safe to use for sensitive data?
This tool uses the browser's native Web Crypto API with AES-256-GCM — the same standard used in TLS and most security applications. However, security also depends on your passphrase strength. Use a long, random passphrase for maximum security. Never use this tool on a device that may be compromised.
What is in the encrypted output?
The output contains three parts joined together: the random salt (16 bytes) used for key derivation, the random IV (12 bytes) for GCM, and the ciphertext with GCM authentication tag. All are encoded as Base64 or Hex depending on your format choice.
Can I decrypt this output in another program?
Yes — the output format is standard. You can decrypt it using OpenSSL or any library that supports AES-256-GCM + PBKDF2-SHA256. The format is: 16-byte salt + 12-byte IV + ciphertext (with 16-byte GCM tag appended).
What if I lose the passphrase?
There is no recovery. AES-256 is computationally infeasible to break without the passphrase. Store your passphrase in a password manager.