AES Decrypt — ECB, CBC & GCM
Decrypt AES-encrypted data using a key you supply. Supports ECB, CBC and GCM, with the common case where the IV sits at the front of the file.
Paste the key you found in the game files
Intended for your own single-player save files. Editing saves in multiplayer or online games breaks their terms of service and can get your account banned. Always keep a backup of the original file before you change anything.
You supply the key — no keys are bundled with this tool. AES-CBC and AES-GCM come from the browser's built-in Web Crypto; ECB is not offered by Web Crypto (it is insecure and leaks patterns), so it is derived from CBC here. Everything runs on your device.
How to use
- 1Load the encrypted data as a file, or paste it as hex or Base64.
- 2Choose the mode, then paste your key in hex, text or Base64.
- 3For CBC or GCM, give the IV — or tick the box if it is the first bytes of the data.
- 4Click Decrypt and inspect the result as text, hex or Base64.
Frequently Asked Questions
Do you provide keys for specific games?
No, and deliberately so. This tool decrypts with a key you supply. Keys extracted from commercial games are documented in the relevant modding communities — no key database is bundled here.
How do I know which mode to use?
Try CBC first, since it is the most common. If the data length is an exact multiple of 16 and there is no obvious IV, try ECB. GCM data usually has a 12-byte IV at the front and a 16-byte authentication tag at the end. Wrong mode means unreadable output, so it is safe to experiment.
What is an IV and where do I find it?
An initialisation vector, 16 bytes for CBC and 12 for GCM, that makes identical plaintexts encrypt differently. It is not secret, so it is very often stored as the first bytes of the encrypted file — tick the box above to use it from there.
Decryption failed. What went wrong?
Almost certainly the key, IV or mode. AES gives no partial credit: one wrong bit produces complete noise rather than nearly-right output. Check whether your key is meant to be read as hex or as literal text, since that is the most common mistake.
Why is ECB offered when it is insecure?
Because games use it, even though they should not. ECB encrypts every block independently, so identical plaintext blocks produce identical ciphertext and patterns leak straight through. Web Crypto refuses to implement it, so it is derived from CBC here.