← ← All Tools

🔐 AES Encrypt/Decrypt

Client-side AES encryption and decryption with GCM, CBC, and CTR modes, PBKDF2 passphrase derivation and raw key input — keys are not uploaded by the tool

All encryption and decryption runs locally in your browser via WebCrypto API. Keys and plaintext are not uploaded by the tool.

Direction

Key Mode

AES key is derived from the passphrase via PBKDF2 (SHA-256, 100,000 iterations).

AES Mode

GCM: Authenticated encryption providing confidentiality and integrity. 12-byte nonce.

Key Size

AAD is not encrypted but is authenticated. The same AAD must be provided during decryption or it will fail.

Output Encoding

FAQ

Why is AES-GCM recommended?

GCM is an authenticated encryption mode that provides both confidentiality and integrity. Tampered ciphertext will fail decryption instead of producing corrupted plaintext. CBC and CTR lack built-in authentication and require a separate HMAC check for integrity.

What is the difference between Passphrase and Raw Key?

Passphrase mode derives the AES key from your password via PBKDF2 (100,000 iterations + random salt), suitable for human-memorable passwords. Raw Key mode uses a hex string directly (128-bit = 32 chars, 256-bit = 64 chars), suitable for interoperability with other systems or programmatic use.

Is my data safe?

All operations use the browser's built-in WebCrypto API and run entirely locally. Keys, passphrases, and plaintext are not uploaded by the tool. Make sure you use this tool in a secure environment and keep the IV and Salt from the encrypted output (needed for decryption).

Free online AES encrypt and decrypt tool — client-side with WebCrypto API. Supports AES-GCM (recommended, authenticated encryption), AES-CBC, and AES-CTR with 128/256-bit keys, PBKDF2 passphrase derivation, and raw key input. Auto-generates IV/Salt with Base64 or Hex output. Keys and plaintext are not uploaded by the tool.