Is it free to use PDF Locker?

Yes, PDF Locker is completely free to use. There are no hidden charges, no signup required, and no watermarks added to your documents.

What encryption does PDF Locker use?

We support AES-256 bit encryption, which is the strongest encryption standard available for PDF documents. This is the same level of encryption used by banks and government agencies.

Are my files safe and private?

Absolutely. Your files are encrypted during transfer using TLS encryption. All uploaded files are automatically deleted from our servers after 1 hour. We never access, read, or share your documents.

What's the difference between an open password and a permission password?

An open password (user password) is required to open and view the PDF. A permission password (owner password) controls what actions are allowed — such as printing, copying, or editing. You can set one or both.

Can I lock multiple PDFs at once?

Yes! You can upload multiple PDF files or entire folders. The same password and restriction settings will be applied to all files. Download them individually or as a single ZIP archive.

Do I need Adobe Acrobat to lock PDFs?

No. PDF Locker works entirely in your browser — no software installation or Adobe Acrobat subscription is needed. It works on Mac, Windows, iOS, Android, and Linux.

Can I remove the password later?

If you know the password, you can use a PDF unlocker tool like pdfunlocker.io to remove the password protection.

Password Protect PDF — Encrypt & Lock PDF Online Free

Add password protection, encryption, and restrictions to your PDF documents. Batch process multiple files at once. Free, fast, and secure.

AES-256 bit encryption

Batch process files & folders

Set open & permission passwords

Restrict printing, copying & editing

Preserve original document quality

No Adobe Acrobat required

Your privacy is protected

All uploaded files are automatically deleted after 1 hour. Files are encrypted in transit and only used for processing. We do not access, read, or share your documents.

Drag & drop PDF files or folders here

or click to browse files

Why choose us

Why Use PDF Locker?

The simplest way to password-protect your PDF documents with enterprise-grade security. No software needed.

Military-Grade Encryption

Protect your PDFs with AES-256 bit encryption — the same standard used by banks and governments. Set open passwords, permission passwords, or both.

Works on Any Device

Lock PDFs online from any browser, on Mac, Windows, iOS, or Android. No software installation required — just upload, lock, and download.

Safe From Start to Finish

Your documents are protected with TLS encryption in transit, and all files are automatically deleted after one hour. Your documents are for your eyes only.

Full Control Over Permissions

Restrict printing, copying, editing, and page extraction. Decide exactly what recipients can and cannot do with your document.

No Signup Required

Start protecting your PDFs immediately. No account creation, no email verification, no credit card. Just upload and secure your files.

Batch Processing

Lock multiple PDFs at once. Upload an entire folder and apply the same protection settings to all files in seconds.

Simple steps

How to Password Protect a PDF Online

Protect your PDF documents in four simple steps. No account required.

Upload Your PDF

Drag & drop your PDF files or folders into the tool, or click to browse and select files from your device.

Set Your Password

Enter an open password, a permission password, or both. Choose your encryption method and restriction preferences.

Configure Restrictions

Select which actions to restrict — printing, copying, editing, page extraction, commenting, and more.

Download Locked PDF

Click "Lock All" and download your password-protected PDF. For multiple files, download them all as a convenient ZIP archive.

Try it now — it's free

Got questions?

Frequently Asked Questions

Everything you need to know about locking and protecting your PDF documents.

Need to Unlock a PDF?

Remove passwords, restrictions, and security from PDF documents with our free PDF Unlocker tool.

Go to PDF Unlocker →

Built by

Sanskar Tiwari

Founder of IndianAppGuy Tech. Shipped 25+ products to 2M+ users, including MagicSlides and SheetAI. I build tools that solve real problems without making you sign up for stuff you don't need.

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