Protect PDF with a Password

To add password to PDF free, add your file to the box above, type a password twice and press Protect PDF. A few seconds later you download a locked copy. Anyone who opens it has to type the password first, in any PDF reader on any device.

You can also keep the file open to read but lock the actions inside it: printing, copying, editing, comments, form filling and page changes. The encryption is AES-256 by default. There is no sign-up, no watermark and no fee, and the file and password are deleted from our server as soon as the locked copy is sent back to you.

To lock PDF from editing, open Permissions and untick Edit the content. Readers can still open and read the document, but a PDF editor that respects the rules will not let them change the text or pictures. Untick Add comments too if you do not want notes or highlights added, and Fill in forms if the fields should stay as they are.

There is one more box worth knowing: Add, delete or rotate pages. Untick it and nobody can remove a page, insert a new one or reorder the document in a normal reader. This is useful for contracts and reports, where a missing page could change the meaning.

If you want the file to open without a password and only block these actions, switch Protection to Only restrict editing. The password you type then becomes the permissions password: it is needed to change the rules, not to read the file.

To prevent PDF from printing, set Printing to Not allowed. The print button in Adobe Reader, Chrome, Edge, Preview and most other apps is then greyed out or refuses to work. This suits drafts, exam papers, paid guides and designs that you want people to see on screen but not on paper.

The middle choice, Low quality, lets people print a rough copy but not a sharp one. A reader that follows the rule prints the page at a low resolution, which is fine for checking a draft but poor for passing off as an original. It is a softer way to discourage reprints without blocking printing completely.

Keep in mind that nothing can stop a person from taking a photo of the screen. Blocking printing makes copying slower and less tempting, which is what most people need.

To protect PDF from copying, untick Copy text and pictures under Permissions. Readers can still see every word, but selecting text and pasting it somewhere else, or saving the pictures out of the file, is blocked in apps that follow the rules.

This is useful for articles, study notes, product sheets, recipes and research that you share for reading only. For stronger protection, combine it with Printing set to Not allowed and Edit the content unticked, so the document can be read but not reused in an easy way.

For a visible sign of ownership on every page, add a mark with Watermark PDF before you lock the file. A watermark stays on screenshots and printouts too, where permissions cannot reach.

Every file you lock here is encrypted. To encrypt PDF with AES 256, simply leave the default setting: AES-256 is the strongest encryption the PDF format supports. Without the password, the content of the file is unreadable data.

Under More options you can switch to AES-128. Pick it only if someone needs to open the file in a very old PDF reader that does not understand AES-256. Both are AES encryption; the number is the key length, and longer means harder to break.

The encryption is done with qpdf, a well-known open-source PDF tool, running on our server. Your file is processed once, the locked copy is sent straight back to you, and both the file and the password are deleted. Nothing is kept.

A PDF can carry two passwords. The user password is the one people type to open the file. The owner password is the one that can change or remove the permissions. You set the owner password under More options, where it is marked as optional.

If you block any permission and leave the owner password empty, a long random one is used. That means nobody, including you, can change those permissions later. If you may want to relax them one day, type your own owner password and keep it safe. When Protection is set to Only restrict editing, the password you typed above is used as the owner password.

A long password matters more than a clever one. The meter under the password box rates it as Weak, Fair, Good or Strong, based on its length and on the mix of small letters, capitals, numbers and symbols. Aim for Strong for anything private.

Tap Make a strong password and the tool creates a random 16-character password with letters, numbers and symbols, and fills in both boxes. It leaves out characters that are easy to confuse, such as 0 and O, or 1 and I. Tap Copy to put it on your clipboard, then save it in your password manager.

Do not send the password in the same email as the file. Send it by text message, say it on the phone or share it in another app. And keep a copy: nobody, including us, can recover a forgotten password.

To protect multiple PDF files at once, select or drop them together, up to 20 per batch. To protect PDF files in a batch, the tool checks each file and shows a label next to it: Not locked, Opens but restricted, Needs a password to open, or Not a readable PDF. Every readable file is then locked with the same password and the same permissions in one run.

When the batch is done, press Download all (ZIP) to save every locked file in one ZIP, or save single files from the list. Each name gets -protected added, so report.pdf becomes report-protected.pdf and you never mix up the locked and unlocked copies. You can turn this off under File names.

If one file fails, for example because it is damaged, the others are still protected and the list shows what went wrong with that one. A Stop button lets you cancel a long batch.

You can set password on PDF online from any browser: Chrome, Edge, Safari, Firefox or Samsung Internet, on a computer, tablet or phone. Nothing has to be installed, and no account is needed.

Your permission choices are remembered in your browser, so the next time you visit the same settings are ready. The passwords are never stored, not in your browser and not on our server. If a PDF is already locked, type its current password next to the file name and the tool will lock it again with your new settings.

Adobe Acrobat Pro can add passwords, but it is a paid app, and the free Adobe Reader cannot do it at all. You can password protect PDF without Adobe right here. The result uses the same AES-256 encryption Acrobat uses, so it opens in Adobe Reader, Acrobat and every other PDF reader exactly the same way.

The permission settings are also the standard ones defined in the PDF format: printing, copying, editing, comments, forms and page assembly. Adobe Reader, Chrome, Edge and Preview all respect them.

To password protect PDF on iPhone or iPad, open this page in Safari, tap Select PDF files and choose the file from the Files app, iCloud Drive, Mail attachments or WhatsApp documents. Type the password, tap the button and save the locked file back to Files or share it straight away.

Recent versions of iOS also have a Lock PDF action in the Files app. It adds a password to open, but offers no permission settings, no choice of encryption and no batches, which is where this page helps.

On Android it works the same way in Chrome or Samsung Internet. Pick the file from your downloads, Google Drive or a chat app, lock it, then share it to WhatsApp, Gmail or Drive.

Locking a PDF has to happen on our server, because the encryption is done with qpdf. Your file and password travel over an encrypted HTTPS connection, the locked copy is sent straight back, and the file and password are deleted right after. We do not keep copies, read your documents or store your passwords.

Before anything is sent, your browser checks each file on your own device to see if it is a real PDF and if it is already locked. Only files you choose to protect are sent, one at a time.

The password to open is the strong part. With AES-256 and a good password, the content cannot be read without it. No reader, editor or website can skip that step.

Permissions work differently. The PDF format asks each app to obey them, and mainstream apps such as Adobe Reader, Chrome, Edge and Preview do. A few editors and converters ignore them, so treat permissions as a strong lock for normal readers, not a vault. If the content is truly secret, use a password to open.

Finally, nobody, including us, can recover a forgotten password. There is no back door. Always keep your original unlocked file and a note of the password in a safe place.

Lock the file last. Merge, compress, sign and watermark first, because most tools need the unlocked file to work with. Merge PDF, Compress PDF, Sign PDF and Watermark PDF all take the original, and protecting is the final step before you share.

Use a different password for each person or group you share with, so one leak does not open everything.

Keep the original unlocked file somewhere safe. If you need to change the password, lock a fresh copy instead of trying to edit the locked one.

Creating a new PDF from Word or images? Turn it into a PDF with Word to PDF or JPG to PDF, then come back here and lock it.

Once your file is locked, share it by email, chat or cloud link as usual, and send the password a different way. The person receiving it opens the file in any PDF reader and types the password once.

If you need to remove the password later, Unlock PDF does it when you know the password. To shrink a big document before you lock it, use Compress PDF, and to send only a few pages, cut them out first with Split PDF.