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Password Protect PDF

Safely Encrypt your PDF Online. Simple and secure way to password protect your PDFs with strong AES 256 bits encryption.

We do not save or store your files on our servers.

Your privacy and data security are important to us.

Free service for documents up to 200 pages or 50 Mb.

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How To Password Protect A PDF

Below we show how to encrypt a PDF file with a password and how to apply PDF restrictions.


Upload your files

Files are safely uploaded over an encrypted connection. Files stay secure. After processing, they are permanently deleted. Click 'Upload' and select files from your local computer.


Choose a strong password

When opening the document, users will be asked to provide this password. Make sure it's a strong password, recommended 16 characters or more.


Optionally, choose an owner password

This is the password that users will be asked when attempting to make changes to the document, after the document is already opened.


Select optional PDF restrictions

Choose what PDF features should be allowed. For example printing can be restricted, or filling forms and commenting can be disabled. Depending on the software used for opening the PDF file, these permissions may or may not be enforced.


Save your changes

Click Encrypt PDF and then Download your protected PDF.

FAQs on Password Protect PDF

Is it possible to encrypt a PDF document with different encryption levels?

Yes, many PDF encryption tools allow you to set different encryption levels and options. For example, you can choose to encrypt only the document contents, or include additional security measures such as password protection, document restrictions, or digital signatures. The available encryption options may vary depending on the tool or library you are using.

What are the common encryption algorithms used for PDF encryption?

PDF encryption commonly uses symmetric encryption algorithms like AES (Advanced Encryption Standard) with different key sizes, such as 128-bit or 256-bit encryption. The encryption algorithm and key size can affect the security level and performance of the encrypted PDF document.

How can I decrypt an encrypted PDF document?

To decrypt an encrypted PDF document, you typically need the correct password or decryption key. You can use a PDF library or tool that supports decryption, such as qpdf, HummusJS, or PDFKit, to provide the password and decrypt the PDF document.

What is the purpose of encrypting a PDF document?

Encrypting a PDF document adds a layer of security by applying encryption algorithms to the document, making it accessible only to authorized individuals who have the correct decryption key or password. Encryption helps protect sensitive or confidential information in the PDF from unauthorized access, ensuring its privacy and integrity.

What types of encryption are commonly used for PDF documents?

PDF documents are typically encrypted using symmetric key encryption or public-key encryption. Symmetric key encryption uses the same key for both encryption and decryption, while public-key encryption involves a pair of keys: a public key for encryption and a private key for decryption.

Can I encrypt a PDF document with a password?

Yes, password-based encryption is a common method for encrypting PDF documents. You can assign a password to the PDF, which will be required to open or modify the document. Password-based encryption typically uses symmetric key encryption algorithms.

Are there different levels of encryption strength for PDF documents?

Yes, PDF encryption can use different encryption algorithms and key lengths, which determine the strength of the encryption. Stronger encryption algorithms and longer key lengths offer higher levels of security but may also result in increased processing time.

Can encrypted PDF documents be cracked or decrypted through brute force?

Strong encryption algorithms and long, complex passwords make it computationally infeasible to crack or decrypt an encrypted PDF document through brute force methods. It is crucial to use strong, unique passwords and employ secure encryption algorithms to ensure the document's security.

Are there any legal considerations when encrypting PDF documents?

The use of encryption and encryption tools may be subject to legal regulations and requirements, depending on the jurisdiction. It is important to familiarize yourself with the applicable laws and regulations regarding encryption and ensure compliance when encrypting PDF documents containing sensitive or confidential information.

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