Password Protect PDF

Novaxera's Protect PDF tool adds an open password to any PDF and encrypts it with AES-256, the strongest encryption defined in the PDF standard. It is free, needs no account, and the password you choose is not stored by Novaxera.

Select a PDF to protect

PDF · up to 50 MB · drag & drop or browse

Encrypting...

This usually takes a few seconds.

Free · No signup · No watermark · Files deleted automatically within 60 minutes

Protect PDF at a glance

The key facts about Novaxera's Protect PDF tool.

Input
One PDF file plus a password of at least 4 characters
Output
PDF encrypted with AES-256
Password type
Open (user) password, required to view the file
After opening
Printing and copying text remain allowed
Compatibility
Adobe Acrobat/Reader, browser PDF viewers, macOS Preview, most modern PDF apps
Price
Free — no signup, no watermark
Max file size
50 MB per file
File deletion
Upload deleted right after processing; result deleted within 60 minutes
Works on
Any modern browser — Windows, macOS, Linux, Android, iPhone

How to password protect a PDF

  1. Upload your PDF

    Select or drag one PDF file of up to 50 MB into the upload box.

  2. Choose a password

    Type a password of at least 4 characters. A long passphrase of 12 or more characters is much harder to guess.

  3. Protect the file

    Start the process and Novaxera encrypts the PDF with AES-256 on its server.

  4. Download and share

    Download the protected PDF, then send the password to the recipient through a different channel than the file.

How Novaxera's Protect PDF works

Novaxera's Protect PDF tool encrypts the whole document with AES-256 and sets the password you type as the open (user) password. Your PDF and password travel to Novaxera's server over an encrypted HTTPS connection. The server writes a new copy of the file in which pages, text and images can only be decrypted with that password, then offers it for download. The original upload is deleted as soon as processing finishes.

A PDF protected by Novaxera asks for the password every time someone opens it, in any reader that supports PDF encryption, including Adobe Acrobat and Reader, the PDF viewers built into browsers and macOS Preview. Once a reader enters the correct password, printing and copying text remain allowed, because the tool sets an open password rather than permission restrictions. Novaxera does not store the password, so a forgotten password cannot be recovered by anyone.

Why use Novaxera's Protect PDF

AES-256 encryption

Files are encrypted with AES-256, the strongest encryption method defined in the PDF standard.

Opens in common readers

Recipients can open the file in Adobe Reader, a browser, macOS Preview or most modern PDF apps after entering the password.

Password not kept

Novaxera uses your password to encrypt the file and does not store it.

Reversible with the password

If you later need an unprotected copy, the same password removes the encryption with Novaxera's Unlock PDF tool.

No watermark, no account

The protected PDF is delivered clean, free and without registration.

Common use cases

Emailing financial documents

Lock tax returns, bank statements or payslips before attaching them to an email.

Sharing contracts

Send a draft agreement to a client so only people who have the password can read it.

HR and personal records

Protect CVs, ID scans or medical letters stored in shared folders or cloud drives.

Client deliverables

Deliver reports to a customer and share the password separately by phone or message.

Limitations to know

  • Novaxera cannot recover a forgotten password, so keep an unprotected copy of the original file somewhere safe.
  • The tool sets only an open password; there are no options to block printing or copying once the file is opened.
  • One PDF is protected per run, with a maximum size of 50 MB.
  • Recipients need a PDF app that supports AES-256, such as Adobe Acrobat/Reader, a browser PDF viewer or macOS Preview.

Tips for better results

  • Use a passphrase of 12 or more characters, such as several unrelated words, rather than a short word or date.
  • Send the password through a different channel than the file, for example by text message when the PDF goes by email.
  • Finish all other changes first: merge PDF files or compress the PDF before protecting it, because those tools need an unlocked file.
  • For a visible ownership mark on top of access control, add a watermark to the PDF before you encrypt it.

Frequently asked questions

How do I password protect a PDF for free?

Upload the PDF to Novaxera's Protect PDF page, type a password of at least 4 characters and download the encrypted file. The service is free, requires no signup and adds no watermark. Each file can be up to 50 MB, and only one PDF is protected per run.

What encryption does Novaxera use to protect PDFs?

Novaxera's Protect PDF tool uses AES-256, the strongest encryption defined in the PDF standard. The file is encrypted with the password you choose, so its contents cannot be read without it. AES-256 protected PDFs open in Adobe Acrobat and Reader, browser PDF viewers, macOS Preview and most modern PDF apps.

Is it safe to password protect a PDF online with Novaxera?

Yes, the process is designed to keep exposure short. The PDF and password are sent over encrypted HTTPS, Novaxera does not store the password, the original upload is deleted once encryption finishes, and the protected result is deleted automatically within 60 minutes. Files are not shared or used for anything else. Details are in the privacy policy.

Can I recover a PDF if I forget the password?

No. Novaxera does not store passwords, so there is no way to recover a forgotten password for a PDF protected with the tool. Before encrypting, keep an unprotected copy of the original file in a safe place and save the password in a password manager.

Can people print or copy text from my protected PDF?

Yes, once they open it. Novaxera's Protect PDF tool sets an open password, so nobody can view the file without the password, but anyone who enters it can still print the document and copy its text. The tool has no option to restrict printing or copying.

How do I remove the password later?

Use Novaxera's Unlock PDF tool to remove the password. Upload the protected file, enter the current password and download a copy that opens without a password. The original password is required; the unlock tool does not guess or bypass passwords.

What is the minimum password length?

The minimum password length on Novaxera's Protect PDF tool is 4 characters. A 4-character password is easy to guess, so a passphrase of 12 or more characters is recommended for anything sensitive, such as financial, legal or medical documents.

Can I password protect a PDF on iPhone or Android?

Yes. Novaxera's Protect PDF tool works in any modern browser on iPhone, iPad and Android, as well as on Windows, macOS and Linux. There is nothing to install: pick the PDF from your Files app or storage, enter a password and download the encrypted file.

Related guides

Related tools

Unlock PDF

Remove a known password from a PDF you are allowed to open

Watermark PDF

Stamp a diagonal text watermark on every page of a PDF

Compress PDF

Reduce PDF size while keeping text sharp and searchable

Merge PDF

Combine two or more PDFs into one document

Edit PDF

Change existing text in a PDF, including Arabic, line by line

Last updated · Maintained by Ghaith Alali · Facts on this page describe how Novaxera's Protect PDF tool currently works. · Privacy policy