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Protect PDF

Add 128-bit AES password protection to your PDF files — free, secure, and no sign-up required.

No Sign-up 128-bit AES Secure & Private
PDF Password Protection
Set a password, upload your PDF, download the protected file
This password will be required to open the PDF.
If left blank, the owner password will match the open password.

Drag & Drop your PDF here

Upload a PDF file to add password protection

Select PDF File

PDF files only — max 100 MB

document.pdf
—
Your files and passwords are processed securely and automatically deleted after download.
Uploading file...
InstantToolsPro is encrypting your PDF…
0%
PDF Protected Successfully
Your PDF is now password-protected with 128-bit AES encryption.
AES
Encryption
128-bit
Key Length
Download Protected PDF
Protected PDF is automatically deleted from our servers after 1 hour.

How It Works

1

Set Password

Enter your open password and confirm it. Optionally set an owner/permissions password.

2

Upload PDF

Drag & drop or click to select your PDF. Up to 100 MB supported.

3

Download

Receive your 128-bit AES encrypted PDF and keep it safe.

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Free Online PDF Password Protection — 128-bit AES Encryption

InstantToolsPro's Protect PDF tool adds industry-standard 128-bit AES password encryption to any PDF file — directly on our secure server, with no software to install and no account required. Set an open password to restrict who can view your document, and optionally set a separate owner password to control editing and printing permissions.

Encryption is handled by Ghostscript or qpdf, the same engines trusted by enterprise PDF workflows worldwide. The resulting PDF is compatible with Adobe Acrobat Reader, Preview, and all major PDF viewers on desktop and mobile.

All uploaded files are processed over a secure encrypted connection and automatically deleted from our servers after one hour. We never read, store, or share your documents or passwords.