Add a password to a PDF with AES-256, without uploading it
Processed in your browser. Nothing is uploaded. Updated on 24 Oct 2026.Adding a password encrypts a PDF with AES-256, so it cannot be opened without one. Worth doing before emailing a contract or an identity document. The encryption happens in your browser, so neither the file nor the password is uploaded. Up to 10 files of 100 MB.
Press Select PDF files and choose the PDF you want to lock.
Type the Password to open the file and type it again in Confirm password.
Optionally set an Owner password and switch off Allow printing, Allow copying or Allow editing.
Press Protect, then Download the AES-256 encrypted PDF; nothing is uploaded.
Protect PDF adds a password to a PDF so it opens only for people who know it. You choose the password, confirm it, decide whether readers may print, copy or edit, and download a copy encrypted with AES-256, the strongest level the PDF standard defines.
People use it before emailing a salary slip, a signed agreement or a medical report, to lock a price list so it can be read but not copied, and to hand out course material that cannot be edited. An optional owner password lets you change the permissions later; without one, a random owner password is generated so the restrictions stay in force for everyone who opens the file with the reading password.
Encryption runs entirely on your device. Neither the file nor the password is sent anywhere, and the password is discarded after the file is written. Up to 10 PDFs per batch, each up to 100 MB and 2,000 pages. Every output is opened again on your device to confirm it really asks for the password before it is offered for download. A file that already has a password is reported so you can remove it first with Unlock PDF.
A lost password cannot be recovered by this tool or anyone else, so keep it somewhere safe. The strength meter is a simple guide: 12 or more characters with a mix of letters, numbers and symbols is a sensible minimum for anything sensitive. Password Generator in the Dev section makes one for you.
Add the PDF, type a password and confirm it, choose whether printing, copying and editing are allowed, and click Protect. Download the copy named after the original with -protected added. It then opens only after the password is entered. No account, no watermark, no upload.
No. The PDF is encrypted by code running in your browser on your own device. The file and the password never leave it, and the password is discarded once the protected copy is written. The page keeps working with your connection switched off.
AES-256 with the standard PDF security handler (revision 5), the strongest level in the PDF specification. It opens in Adobe Reader, Chrome, Edge, Firefox, Preview on macOS and iOS, and current Android viewers. Very old readers from before 2009 may not support AES-256.
The password, sometimes called the user or open password, is what readers type to open the file. The owner password is optional and lets you lift the permission limits later. If you leave it empty a random one is generated so the permissions cannot be removed by readers.
Yes. Switch off Allow copying or Allow printing before you click Protect. Readers who open the file with the password can still read it but their viewer blocks copying or printing. Accessibility extraction for screen readers stays on. Note that a determined person can always photograph a screen; permissions deter, they do not prevent.
Up to 10 PDFs at a time, each up to 100 MB and 2,000 pages, and passwords from 4 to 128 characters. A PDF that already has a password must be unlocked first with Unlock PDF. A forgotten password cannot be recovered, so keep it somewhere safe.
PDF ko password se surakshit banaye: type a password, confirm it, decide whether printing, copying and editing are allowed, then press Protect. The copy is encrypted with AES-256. Up to 10 PDFs at a time, each 100 MB, with passwords from 4 to 128 characters. A lost password cannot be recovered by anyone.
Still stuck? Ask about Protect PDF and anybody who knows can answer. No account needed.
Also works as: Password Protect PDF.
Same job, other tools: Decrypt File – Open a .enc file encrypted here, with its password · Unlock ZIP – Remove the password from a zip you can already open · HEIC to PDF – Convert iPhone HEIC photos straight into a PDF · JPG to PDF – Convert JPG photos into a single PDF, in the order you choose · Compress PDF to 500 KB – Fit a multi-page scan under 500 KB with its text still readable · Compress PDF to 50 KB – Get a one-page scan under 50 KB for strict document uploads.
In the collections PDF Converter · PDF Tools · Privacy and Protection Tools.