Encryption Key Generator

Generate an AES encryption key

Symmetric encryption with AES, the Advanced Encryption Standard, requires a secret key of 128, 192 or 256 bits. This generator produces a cryptographically random AES key of your chosen size, shown in both hexadecimal and base64, along with a random 128-bit initialisation vector, which most AES modes need to ensure that encrypting the same data twice produces different output. AES-256 offers the strongest key size and is the common choice for sensitive data.

The random bytes come from the browser secure random generator where available, which is essential because a predictable key undermines the entire encryption.

Keys and initialisation vectors

The strength of AES depends on the key being truly random and kept secret; the algorithm itself is public and trusted. The initialisation vector, by contrast, does not need to be secret but should be random and unique for each encryption, which prevents an attacker from spotting repeated plaintext. Reusing an IV with the same key is a classic and serious mistake, so generate a fresh IV for every message.

Store the key securely and transmit it only through protected channels, never alongside the ciphertext in the clear. The values here are generated locally and never sent anywhere. All generation happens locally in your browser.

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