Protect PDF

Overview

Add a password to a PDF with AES-256 encryption. A strength meter helps you pick a good one, and you can block printing, copying or editing. The encryption runs in your browser using qpdf, so your document and password never leave your computer.

Financial documentsLock statements, tax forms or payslips before you email or store them.
Confidential contractsEncrypt a contract so only people with the password can open it.
Limit reuseBlock copying and editing on a document you share.
Personal recordsPassword-protect medical records, IDs and other personal PDFs on a shared computer.
Print-only formsAllow printing but block editing and copying on forms you hand out.

Key features

AES-256 encryption
Confirm field and strength meter
Limit printing, copying and editing
Runs in your browser
Nothing is uploaded

Set

PDF Tools 17

Neighbours

01 Add Page Numbers to PDF 02 Compress PDF 03 Delete PDF Pages 04 Extract PDF Pages 05 Fill and Sign PDF 06 JPG to PDF

Specification

Command: pdf.protect_pdf
Set: PDF
Input: PDF
Output: PDF
Max file: 500MB
Batch: single file

Runtime

Engine: pdf-lib · pdf.js · qpdf-wasm
Threads: single
Isolated: —
WebGPU: —
Memory: —

Transport 0 B

Your file is opened, worked on and saved inside this tab. This tool has no upload step, so your file has nowhere else to go.

Keys

Search: ⌘K
Panels: ⌘1 · ⌘2
Full width: F
All keys: ⌘/

How it works

Open your PDF

Drop in the PDF you want to protect.

Set a password

Pick a strong password and, if you like, block printing, copying or editing.

Download

The PDF is encrypted with AES-256 and saved to your computer.

Frequently asked

What encryption is used?

AES-256, the strongest standard PDF encryption. Anyone who opens the file needs the password you set.

Is the encryption done in my browser?

Yes. It runs on your computer with qpdf compiled to WebAssembly, so neither your PDF nor your password is uploaded.

What do the permission options do?

They decide what people can do once they've opened the file: print, copy text or edit. Most PDF readers respect these settings.

What if I forget the password?

It can't be recovered. The encryption is strong on purpose, so keep your password somewhere safe.

Can I protect an already-encrypted PDF?

Remove the current password first with Unlock PDF, then protect it again with a new one.

Keys

Search: ⌘K
Panels: ⌘1 · ⌘2
Full width: F
All keys: ⌘/