All tools

Encrypt a File with a Password: AES-256 Encryption in Your Browser

Protect a private file before you email it, store it in the cloud or carry it on a pen drive. Choose any file (PDF, photo, spreadsheet, ZIP…), type a strong password and get a locked copy that nobody can open without it. To open it, drop the locked file here on any device and type the password. Encryption uses AES-256-GCM with a key stretched from your password 310,000 times, and nothing ever leaves your browser.

loading tool

How to encrypt a file with a password

  1. Choose the file you want to lock.
  2. Type a strong password twice.
  3. Press Lock file and download the .locked copy.
  4. To open it later, choose the .locked file here, type the password and press Unlock file.

Good to know

  • The original file name is locked inside too, so the locked copy does not reveal what it contains.
  • If even one byte of the locked file changes, unlocking fails instead of giving you a damaged file.
  • For short secrets like Wi-Fi passwords or bank details, the Encrypt Text tool gives a code you can paste into a chat.

Questions

How secure is it?

AES-256-GCM is the standard used by banks and governments, and the 310,000 rounds of PBKDF2 make guessing passwords very slow. The real weak point is the password: use 12 or more characters, or four or five random words.

What if I forget the password?

The file cannot be recovered: there is no back door, not even for us. Keep the password in a password manager.

Can the receiver open it without this site?

They need this tool (it works on any phone or computer, free and without sign-up) and the password. Send the password separately, for example by phone call, not in the same email as the file.

Is my file uploaded?

No. The file is read by your own browser and never leaves your device, so it is safe to use with private documents. It also works offline once the page has loaded.

Is my data private?

Yes. Everything happens inside your own browser: nothing you type or choose is uploaded to us or anyone else.

Is it free?

Completely free, with no sign-up, no watermark and no limit on how many times you use it. Light ads keep the site running.