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Mofumi PDF

Protect PDF

Lock a PDF with a password using AES-256 encryption and choose what readers may print, copy or edit.

100% Private — files never leave your device
Upload PDFDrop files here or click to chooseAccepted: PDF Files never leave your device

About this tool

Protect PDF encrypts your document with AES-256, the strongest encryption defined by the PDF standard and the one recommended by ISO 32000-2. Anyone who opens the file must enter the password you set; without it the contents are unreadable, not merely hidden.

You can also set permissions: allow or block printing (and high-quality printing), copying text and images, editing, adding comments, filling forms, accessibility tools and page assembly. Permissions are protected by a separate owner password. If you leave it empty, a strong random owner password is generated and thrown away, so the restrictions cannot be lifted with the file alone.

Everything happens in your browser. Your PDF and your passwords never leave your device and are forgotten as soon as the file is ready. Choose AES-128 only if the file must open in very old PDF readers.

Engines: pdf-lib

How to use

  1. 1

    Upload the PDF you want to protect.

  2. 2

    Enter an open password and, if you like, an owner password and permissions.

  3. 3

    Click Protect PDF and download the encrypted file.

Use cases

  • Send payslips and statements

    Email salary slips or bank statements that only the recipient can open.

  • Share confidential reports

    Lock board papers or HR documents and stop recipients from copying text.

  • Protect personal records

    Encrypt scans of ID cards, contracts or medical records before storing them in the cloud.

Frequently asked questions

How strong is the encryption?

AES-256 with the PDF 2.0 security handler. With a good password it is not practical to break; the password itself is the weak point, so use a long one.

What is the owner password for?

It controls the permissions (printing, copying, editing). Readers that respect the PDF standard enforce these restrictions unless the owner password is entered.

I forgot the password. Can you recover it?

No. Nothing is stored anywhere, and AES-256 cannot be reversed. Keep a copy of the original file or the password.

Are my files uploaded?

No. Encryption runs locally in your browser; the file and passwords never leave your device.

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