PDF Tools
Lock, password protect and encrypt your PDF with strong AES security — right in your browser. Set an open password, an owner password, and exactly what others can print or copy.
Your files are 100% Protected & Safeor browse your device — add a password and encryption
No upload size limit · AES-256 encryption · 100% freeYour PDF is encrypted on your own device — never uploaded.
Open password *
Confirm password *
Control printing, copying and editing (optional)
Encryption strength
Owner password (optional)
What others are allowed to do
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Lock your document in three quick steps.
Drop a PDF into the box, or browse to select it from your device.
Type an open password and confirm it. Optionally set an owner password and permissions.
Click Protect PDF and download your encrypted, password-protected file.
Need to password protect a PDF before you email or share it? This free tool adds a password and AES encryption to your document entirely in your browser, so the file is never uploaded to a server and there are no size limits.
Set an open password that is required just to view the PDF, and — if you need finer control — an owner password with granular permissions: allow or block printing, copying text, editing, annotating, form filling and page assembly. Choose 256-bit or 128-bit AES encryption. The result is a properly encrypted PDF that opens in Adobe Acrobat, Chrome, Preview and every standard reader — no sign up, no watermark, completely private.
Enterprise-grade security without Acrobat — free and private.
Military-grade 256-bit AES, the same standard banks and governments use.
Require a password to view, plus a separate owner password for permissions.
Allow or block printing, copying, editing, annotating, forms and assembly.
Your PDF is encrypted on your own device and never sent to any server.
The encrypted PDF opens in Acrobat, Chrome, Edge, Preview and all readers.
No account, no watermark, no limits. Protect as many PDFs as you like.
Round out your workflow with the rest of our toolkit.
Add your PDF, type an open password and confirm it, then click Protect PDF. Your file is encrypted in the browser and downloads as a password-protected PDF. You can also set an owner password and permissions under Advanced.
The open (user) password is required just to view the PDF. The owner password controls permissions such as printing and copying; someone who opens the file with only the open password is held to those restrictions. If you leave the owner password blank, the open password is reused.
The default is 256-bit AES, the same encryption standard trusted by banks and governments. You can also choose 128-bit AES. The strength of your protection still depends on choosing a strong, unique password.
Yes. Open Advanced and set permissions: allow, restrict to low-quality, or block printing, and toggle copying text, editing, annotating, form filling, page assembly and accessibility extraction. Note that permission restrictions are enforced by the PDF reader.
Yes. It uses the standard PDF security handler, so it opens in Adobe Acrobat, Chrome, Edge, Apple Preview and every conforming reader. Anyone with the password can open it.
There is no way to recover it - that is the point of strong encryption. Store your password somewhere safe, such as a password manager, before you share the file.
Completely. There is no account, no watermark and no limit. Everything runs in your browser using WebAssembly, so your PDF and password never leave your device.
To encrypt without a server, the tool loads a small open-source encryption engine (qpdf) into your browser the first time you protect a file. It is then cached, so later files are instant. Nothing about your PDF is ever uploaded.