PDF Password Protector
Put a password on a PDF before you send it. The document is encrypted on your own device; the password is never transmitted anywhere.
Click to choose a PDF, or drag & drop it
PDF only · encrypted in your browser, never uploaded
Anyone opening the document will be asked for this. It is the password that actually matters.
Controls who may change the permissions below. If you leave it blank, the open password is used for both.
Permissions
Done
What this tool does
This tool encrypts a PDF so that opening it requires a password, and optionally restricts what a reader can do with it afterwards — printing, copying text and images, and editing.
The encryption happens in your browser. Your file is not uploaded and your password is not sent anywhere: there is no server involved and no copy of either on this site. That is the privacy advantage, and it comes with a matching responsibility — there is also no password recovery of any kind. No reset link, no support process, nothing to fall back on.
Two passwords are involved. The open password is the one a reader is asked for. The owner password controls who can change the permissions; if you leave it blank, the open password is used for both.
How to use it
- Drop in your PDF.
- Type the password to open the file. Confirm it by revealing it briefly if you want to check for typos — a typo here is unrecoverable.
- Optionally set the permissions, and an owner password if you want the restrictions to be changeable by someone else.
- Press Protect PDF. The encrypted copy downloads straight away. Keep the password somewhere safe before you close the page.
Common use cases
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Sending a confidential document
Email a contract, a payslip or a bank statement so that the attachment is useless to anyone who intercepts it.
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Limit what a recipient can do
Allow reading and printing but block copying of the text, or block printing entirely.
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Client and patient material
Add a second layer of protection to files that are already being sent over an unencrypted channel.
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Stored copies
Protect an archive of identity documents sitting on a shared drive or a USB stick.
Frequently asked questions
Can ToolStack AI recover the password if I lose it?
No. The password is never transmitted, stored or logged — it exists only in your browser for the few seconds it takes to encrypt the file. There is no mechanism that could recover it, by design. Save it in a password manager before you press the button.
How strong is the encryption?
The document is written with the PDF Standard Security Handler using AES encryption, which is what Acrobat, Preview, and every mainstream reader expects. The encryption is genuinely strong; the weak point in practice is almost always the password you choose, so use a long one.
What happens if the encryption engine will not load?
The tool stops and tells you so, and downloads nothing. That is deliberate: the alternative would be handing back the original unencrypted file with a success message, which is the one outcome that could genuinely hurt someone. Check your connection and try again.
Does this work on a PDF that is already password-protected?
Not without the password. Use the PDF Unlocker first if you know it; if you do not, the file cannot be opened here at all.