AES-256 encryption
Add an open password using modern AES-256 PDF encryption.
Protect PDF
Add an open password to your PDF with AES-256 encryption and optional document permissions.
Choose a PDF
Drag and drop your PDF here, or browse files
One PDF · Up to 200 MB · No daily limit · Unlimited use
PDF password protection
Encrypt a PDF without changing its page layout
PDFPA applies encryption to the PDF itself, helping restrict document access while preserving the existing text, images, vector graphics and page appearance.
Optional permissions
Control whether password-level users may print, copy, edit or annotate the protected document.
Original PDF content preserved
Protection does not require rasterizing the document, so the original page structure remains available.
Temporary password handling
The password is kept only for the processing workflow and is removed from the temporary worker secret as processing starts.
How to password protect a PDF
Add PDF encryption in three steps.
Upload your PDF
Choose one PDF up to 200 MB.
Set the password
Enter and confirm the open password, then optionally adjust printing, copying, editing and annotation permissions.
Download the protected PDF
Download the encrypted output during the temporary result window.
Temporary processing for password-protected PDFs
PDFPA creates a separate protected copy and leaves the original file on your device unchanged.
Password kept out of normal job metadata
The open password is handled separately from ordinary processing settings and removed from the temporary secret file when the worker begins.
Automatic cleanup
Uploaded files and generated results follow the normal temporary processing and deletion lifecycle.
Free PDF password protector
Add password protection when a PDF needs controlled access
Password protection can help when you are sharing reports, client files, internal documents or other PDFs that should not open freely. PDFPA lets you encrypt a PDF online without rebuilding the pages or converting the document into images.
Use AES-256 encryption for PDF access protection
The open password is required when someone tries to open the protected PDF. PDFPA uses AES-256 PDF encryption so the document can remain a normal PDF while access is restricted by the password you choose.
Because the protection is applied to the PDF structure, the existing page layout, selectable text, images and vectors can remain intact rather than being re-rendered.
Control common document permissions
PDF permissions let you specify whether password-level users may print, copy, edit or annotate the file. These controls are useful for document workflow and policy enforcement, although behavior can still depend on the PDF reader used by the recipient.
Keep the original unprotected document in a safe location. If you forget the password, PDFPA cannot recover it later after the temporary processing data has been deleted.
Free online PDF protection without a daily allowance
Protect PDF can be used without a public account, subscription or payment. There is no daily protection quota to use up, while each job remains subject to the per-file size limit and normal abuse protections.
For a document that is already encrypted, unlock it with the correct existing password first, then apply your new password and permissions to the resulting file.
Quick answers
Protect PDF FAQ
Common questions about PDF passwords, AES-256 encryption and permissions.