🔐 AES Encryption
Encrypt and decrypt text with AES-256-GCM. Runs entirely in your browser via the Web Crypto API — nothing is sent anywhere.
How it works
Your passphrase is stretched into a 256-bit key with PBKDF2 (SHA-256, 210,000 iterations) using a random 16-byte salt. The text is then encrypted with AES-256-GCM using a random 12-byte IV.
The output is base64(salt || iv || ciphertext) — a single self-contained string. Paste it back into the Decrypt tab with the same passphrase to recover the original text.
Encrypt and decrypt text with AES-256-GCM using your browser’s built-in Web Crypto API. Your passphrase is stretched with PBKDF2 into a key, and the output packs the salt, IV and ciphertext into a single base64 string — nothing you type ever leaves your device.
Frequently asked questions
How secure is this encryption?
It uses AES-256-GCM, a modern authenticated cipher, with a key derived from your passphrase via PBKDF2 — the same primitives used by mainstream security software, provided natively by your browser’s Web Crypto API. The practical weak point is the passphrase: a short or guessable one undermines any cipher, so use a long, random passphrase.
What happens if I enter the wrong passphrase when decrypting?
Decryption simply fails with an error. GCM is authenticated encryption, so a wrong passphrase (or tampered ciphertext) is detected and no garbled output is produced — you either get the exact original text or nothing.
What is the format of the encrypted output?
The output is base64 text containing the random salt, the IV and the ciphertext together. That single string is all you need to decrypt later — paste it back with the same passphrase. There is no way to recover the text if the passphrase is lost.
Can I use this for company secrets or regulated data?
It is genuinely strong encryption and fine for personal notes and everyday sharing, but it is not a managed secrets platform — there is no key management, access control, audit trail or recovery. For regulated data or secrets at scale, use purpose-built infrastructure.