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Protect PDF

Add a password to a PDF and choose what readers are allowed to do with it — print it, copy text out of it, or change its pages. The encryption happens on your own device.

Files are never uploaded

How to use it

Add the PDF

Drop the file above, or click to browse. If it is already password-protected, remove that password first with Unlock PDF.

Set the open password

Type the password readers will need in order to open the file. Leave it blank when you want anyone to open the document but still want to control printing, copying and editing.

Choose the permissions

Decide whether readers may print, copy text and images, or edit the pages. Anything left switched off is blocked in readers that honour PDF permissions.

Protect the file

Press Protect PDF. The document is encrypted in your browser with the strength you selected — 256-bit AES unless you change it.

Download and test

Download the protected file and open it once to confirm the password prompt appears. Keep an unprotected original: a forgotten open password cannot be recovered.

Common issues

A forgotten open password locks you out for good

There is no recovery path, because the file really is encrypted. Keep an unprotected copy of anything you may still need to work on.

Permissions are a request, not a guarantee

Printing and copying restrictions are honoured by well-behaved readers and can be circumvented by others. Use them to prevent accidental changes, not as a substitute for the open password.

Protecting an already-protected file fails

The tool reports that the document is already encrypted. Unlock it first, then apply the new protection.

Very old readers and 256-bit AES

A handful of legacy programs cannot read 256-bit AES. If the file has to open in an old reader, choose 128-bit AES instead.

Frequently asked questions

How strong is the encryption?
The default is 256-bit AES, the strongest encryption the PDF format supports and what modern readers expect. A 128-bit AES option is available for very old software.
What happens if I leave the open password blank?
The file opens without a prompt for anyone, but the permissions you set still apply: readers that honour PDF permissions will refuse to print, copy or edit them as you chose.
What is the owner password for?
It is the password that unlocks the permissions themselves, so the restrictions can be changed later. Left blank, it is set to the same value as the open password.
Can I recover a PDF if I forget the open password?
No. The encryption is real, so a forgotten password means the document cannot be opened — not here and not anywhere else. Always keep an unprotected copy.
Do the permissions actually stop people?
Permissions are enforced by the reader rather than by the file, so a determined person with the right tool can bypass them. They are useful for setting expectations and preventing accidental changes; rely on the open password for genuinely sensitive content.
Does protecting the file change its contents?
No. The pages are encrypted as they are, so text stays selectable in a reader that is allowed to copy, and nothing is re-compressed or re-rendered.
Is my password sent anywhere?
No. The document and both passwords are handled inside your browser. Nothing is uploaded and no copy is kept.
Can I protect a file that is already password-protected?
Not directly. Remove the existing password with Unlock PDF, then protect the file again with the settings you want.
Will protected files open on phones and in email attachments?
Yes. The result is a standard encrypted PDF, so it opens in any reader — desktop, mobile or web — and asks for the open password wherever it is used.

Related tools

Unlock PDFGot a PDF that asks for a password every time you open it? Type that password once and download a copy that opens freely — the document never leaves your device. Edit PDF MetadataChange the hidden document information a PDF carries — the title shown in a browser tab, the author, the keywords — or strip it all out before you share the file. Watermark PDFStamp a word or phrase across every page — CONFIDENTIAL, DRAFT, your company name. Decide how strong it looks, then download. Merge PDFCombine several PDFs into a single document in the order you choose. Everything runs inside your browser.

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About this page. Written and maintained by the AI-Mind team. Last reviewed 11 October 2026. This tool runs entirely in your browser. Found an error or have a suggestion? Use the feedback form above or email [email protected].