Apchukso ~/protect
All tools Protect PDF Compress PDF
● No upload · Your password never leaves the browser
English
TOOL / PDF LOCK

Keep prying eyes out.
Lock your PDF.

Add a password and only people who know it can open the PDF. You can also remove a password.

Drop a PDF here or click to choose
1 PDF file
🔒
Your files never leave your device. Apchukso has no server that receives files. Everything is processed right here in this browser.
How to check for yourself
  1. With this page open, turn off Wi-Fi and try it. It still works.
  2. Press F12 → open the Network tab and run it. Aside from small analytics requests, there's no transfer anywhere near the size of your file.
Next steps
How it works: The open-source pdf-lib (cantoo fork) library encrypts and decrypts with AES-256 directly, using the browser's built-in Web Crypto API. Your password is never sent anywhere.

More about PDF password protection

Use it when you need to email sensitive documents like contracts or pay stubs, when you want to restrict access before putting a file in a shared folder, or, the other way around, when you open a password-protected PDF so often that you'd rather remove the password for good.

How to use

  1. Choose "Add password" or "Remove password" mode
  2. Choose a PDF
  3. Enter the password, click the button, and download the result

FAQ

Q. What if I forget the password?

Apchukso doesn't store your password, so if you forget it, there's no way to recover it. Write it down somewhere safe.

Q. What kind of encryption does it use?

It uses AES-256, the industry standard. Most PDF viewers, including Adobe Acrobat, will ask for the password as expected.

Q. Is my password sent to a server?

No. Neither the password you enter nor your PDF ever leaves the browser. Encryption happens right in the browser, too.

Q. Can I remove a password, too?

Yes. On this same page, switch to "Remove password" mode and enter the password to save the PDF again without the lock.

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