Password Protect PDF
Add a password to your PDF so it cannot be opened without it.
Select PDF file
or drop PDF here
Files are processed securely in your browser.
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How to password protect a PDF
Before you email a contract, an ID copy or a financial document, you can lock it so that it only opens with a password.
Most online tools make you upload the unprotected file first. Arcanize adds the password inside your browser, so the unlocked document never leaves your device.
Nothing leaves your device: The file is encrypted locally in your browser.
Password required to open: The protected PDF asks for your password in any PDF reader.
Add a password to a PDF in 4 steps
- Click Select File and choose the PDF you want to lock, or drop it onto the page.
- Type the password you want to set.
- Click Protect PDF.
- Click Download File to save the locked copy, and keep the original somewhere safe.
Good to know
- One PDF at a time.
- There is no way to recover a forgotten password, so keep the original file or store the password safely.
- The file is locked with standard PDF password encryption. A short or guessable password can still be guessed, so use a long one.
- The first run takes longer because your browser downloads the processing engine (up to 14 MB).
Frequently asked questions
How do I add a password to a PDF for free?
Select the PDF on this page, type a password, click Protect PDF and download the locked copy. It is free and needs no account.
Can someone open the PDF without the password?
PDF readers will ask for the password before showing the document. How well it resists guessing depends on the password, so avoid names, birthdays and short words.
What happens if I forget the password?
It cannot be recovered. Keep the original, unprotected file in a safe place or save the password in a password manager.
Is my document uploaded when I protect it?
No. The password is added by your browser on your own device. Arcanize never receives the file or the password.
How should I share the password?
Send it through a different channel from the file. For example, email the PDF and send the password by SMS or a phone call.
Related PDF tools
- Unlock PDF – Remove the password from a PDF when you know it.
- Compress PDF – Reduce PDF file size with three compression levels.
- Merge PDF – Combine multiple PDF files into one, in the order you choose.