What is AES encryption?
AES is the standard cipher used to protect data around the world. This tool uses AES-GCM, which also proves the contents have not been changed.
Which AES key size should I use?
Use AES-256, the default. AES-128 is a little faster and still safe. There is no AES-192 because Chromium's Web Crypto does not accept 192-bit keys.
What happens if I use the wrong key?
The tool tells you, instead of handing you a corrupt file. If a later block fails, the key was right and the file itself has been altered. Nothing is saved when a check fails.
How should I manage my encryption keys?
Keep the key somewhere other than the encrypted files. Save it as a key file, or put it in a password manager, on another drive or on paper.
Is my data secure during encryption?
Yes. Everything runs in your browser through the Web Crypto API. Your files, key and password never leave your computer, and the tool works offline.
Can I encrypt files as well as text?
Yes. Drop any file, or paste text into the box under the drop zone. Text comes back as base64 you can paste into a message, and files come back as a download.
How large a file can I encrypt?
There is no fixed limit, because files are processed in 1 MiB blocks. The real ceiling is how much your browser will store for the result. If you reach it, the tool tells you and saves nothing.
What happens if I lose my encryption key?
Then the data is gone. There is no recovery and no back door, which is what makes the encryption worth having. Save the key before you close the tab.
