Free · No limits · Client-side

Protect PDF.

Add password to PDF free online — encrypt and protect your PDF files with a password. No login, no signup, unlimited use, and no upload: files never leave your browser.

Files never leave your browserNo waiting for server uploadsUnlimited — no daily caps

Drop a PDF here

or click to browse

Processed locally · never uploaded

How to use

Step 01

Upload your PDF

Drag and drop a PDF file into the upload area, or click to browse and select it from your device.

Step 02

Set a password

Choose a password and confirm it. A strength indicator helps you pick something secure. Both the password and confirm fields must match.

Step 03

Download the protected PDF

Click "Protect PDF" and your browser encrypts the file locally. Download the password-protected version — it is never sent to any server.

Add password protection to your PDF

A protect PDF tool takes an unprotected PDF document and encrypts it with a password, so that only someone who knows the password can open it. This is essential for any document you plan to share that contains sensitive, confidential, or personal information. pdfEditor lets you add password to PDF free directly in your web browser with no software to install and no account to create.

Because this is a genuinely free PDF encryption tool, there are no daily task limits, no watermarks, and no "upgrade to Pro" paywall. You can protect a single file or process several in a row, as often as you need.

Why protect a PDF with a password?

People need to encrypt PDF free for all sorts of everyday reasons: securing a financial statement before emailing it, protecting a signed contract shared via cloud storage, locking down a medical report that will be sent to multiple recipients, or adding a layer of security to tax documents stored on a shared drive. Password protection ensures that only authorized people can view the content.

Doing this online without an account matters when the document itself is sensitive. The irony of uploading a confidential file to someone else's server — just to add a password — is not lost on anyone. With a client-side tool you get to protect PDF online while the file never leaves your own device.

How to add a password to a PDF free online

  1. Upload your PDF. Drag and drop the file into the upload area above, or click to browse and select it.
  2. Choose a password. Type a password and confirm it. The strength indicator helps you pick something secure.
  3. Protect and download. Click "Protect PDF" and your browser encrypts the file locally, producing a password-protected copy ready to download.

That is the entire process to add password to PDF online — no email address, no server processing, and no queue.

Frequently asked questions about PDF password protection

Is this protect PDF tool really free? Yes. It is a secure PDF free tool with no hidden tier — no signup, no subscription, and no per-day cap on how many files you can encrypt.

Can I protect a PDF without login? Absolutely. There is no login of any kind. You open the page and start working immediately, which is exactly what people searching for secure PDF free no login are looking for.

Will the password protection work in all PDF readers? Yes. The encryption is compatible with Adobe Acrobat, Preview, Chrome's built-in viewer, Firefox, and all standard PDF applications.

Can I set different passwords for opening and editing? Currently the tool sets the same password for both open and owner access. This is the most common use case — preventing unauthorized people from opening the document at all.

Private by design

Every encryption happens entirely in your browser using JavaScript — your files and the password you choose are never uploaded to a server, stored, or transmitted anywhere. The moment you close the tab, nothing remains. That is what makes this a safe way to protect PDF online free: the privacy is inherent in the architecture, not just a policy promise. You can verify it by opening your browser's Network tab and watching for zero outgoing requests while you encrypt.

Tips for strong password protection

Choose a password that is at least 8 characters long and includes a mix of uppercase letters, lowercase letters, and numbers. Avoid using obvious passwords like "password", "123456", or the name of the document. The strength indicator in the tool will help guide you toward a secure choice.

After downloading the protected PDF, make sure to share the password through a separate channel — do not include it in the same email as the file. And keep a note of the password somewhere safe, because once the file is encrypted, you will need the password to open it. If you forget it, you can use the Unlock PDF tool to remove it — but only if you remember or recover the password first.

Frequently asked questions

What type of encryption does this tool use?

The tool uses PDF-standard encryption supported by pdf-lib, which is compatible with all major PDF readers including Adobe Acrobat, Preview, Chrome, and Firefox. The encrypted file will require the password you set to be opened.

Can I remove the password later?

Yes. Use the Unlock PDF tool on this same site. As long as you remember the password you set, you can remove the protection at any time and download an unencrypted copy.

Are my files and password uploaded to a server?

No. The entire encryption process happens locally in your browser using the pdf-lib JavaScript library. Neither your file nor the password you type is ever sent, queued, or stored anywhere. You can confirm this by checking your browser's Network tab during the process.

What happens if the PDF is already password-protected?

The tool will detect the existing protection and let you know. To change the password, first use the Unlock PDF tool to remove the current password, then return here to add a new one.

Is there a minimum password length?

The tool requires at least one character, but the password strength indicator encourages you to use 8 or more characters with a mix of uppercase letters and numbers for strong protection. A stronger password means better security.