Protect PDF Documents Online for FREE

Our online tool allows you to password protect PDF documents online for free
Drag & Drop the File(s) Here
Choose File

How It Works?

Upload your PDF

Select a PDF from your computer or cloud storage or just drag and drop a PDF into the box above

Easily Encrypt a PDF online

Password protect your PDF documents against unauthorized access. Allow only trusted recipients to open and edit your documents.

Protect PDFs in the Cloud

Our service allows you to encrypt PDF documents without having to install additional software to your computer. Save time protecting your documents online.

Absolutely Free

Forget about expensive software and time-consuming downloads. AltoProtectPDF allows you to protect PDFs online and absolutely for free.

Keep PDFs Secure

AltoProtectPDF keeps your PDF documents private. All documents are securely uploaded and processed. Once you’ve encrypted a PDF with a password and downloaded it, it will be deleted from our server.

Encrypt PDFs on any Platform

AltoProtectPDF is compatible with major operating system like Windows, Mac OS and Linux. You can easily password protect PDFs on any internet connected device in seconds.

Characteristics

File extension .pdf
Internet media type application/pdf
Description: The Portable Document Format (PDF) is a vector-based file format introduced by Adobe Systems in 1993. It was primarily designed for opening and editing documents on various desktop and mobile devices regardless of the operating system installed. PDFs can contain both text and images. Every page of a PDF file has a fixed layout and retains its structure when shared, printed, or downloaded to another device.
Technical Details: A PDF is a 7-bit ASCII file. It is based on the PostScript language and contains the description of a flat document with a fixed layout and all the embedded elements, such as graphic objects and fonts (in case the file includes text sections). PDF documents may also contain fillable fields, as well as interactive elements, i.e. hyperlinks, bookmarks, buttons, etc.
Developed by ISO
Initial Release: 15 June 1993
Useful links: https://acrobat.adobe.com/us/en/acrobat/about-adobe-pdf.html
https://fileinfo.com/extension/pdf

 

Customer Questions and Answers

Question:
Hi, I’m looking for a reliable online solution that would prevent converting a PDF file that I own to another text or graphic format.
Answer:
I would suggest that you encrypt your file. By doing so, you are able to control access to your PDF and choose which users are allowed to view it and which are not. Go to AltoProtectPDF.com and assign a unique password to your document. It won’t take more than a few seconds at most.
By Andrew on May 02, 2018
Question:
Is there any trusted software for password-protecting a PDF invoice for free?
Answer:
No worries! With www.altoprotectpdf.com you are able to password-protect your PDF effortlessly. It’s fast, reliable and free. Besides, there are many other tools you can apply to it once it’s ready.
By John on April 11, 2018
Question:
Does anybody know how I can encrypt a contract in PDF format so it can’t be viewed by a third person?
Answer:
I know this nice and convenient web tool called AltoProtectPDF. They allow you to upload an unlimited number of files and it literally takes a few second to process your PDFs and have them password-protected.
By Charlene on March 23, 2018
See All Question

How Do Users Rate AltoProtect?

Our service faciliates the work of over two million people protecting PDF documents online every year.

4.5
1,235Votes

How to Protect PDF Files from Theft

Have you been looking for a quick and convenient solution for preventing your data from unauthorized access and falling into the wrong hands? Do you want to choose which users are able to view and edit your files and which are not? With AltoProtectPDF you can protect PDF documents effortlessly. It’s a powerful and free web platform that enables you to set unique passwords for each of your PDFs. AltoProtectPDF increases the security of your information and helps you organize your workflow digitally.

Forget about paid software! There’s no longer any need to download unnecessary programs and plugins to your device. Neither will you have to worry about your space on your hard drive being used up. AltoProtectPDF enables you to use your time wisely and eliminate paper clutter once and for all. It combines both a simple, intuitive interface with a powerful toolkit accessible from any internet-connected desktop or mobile device. It doesn’t matter if you’re a beginner or advanced user, our free online platform has been designed to suit your needs.

How to Protect a PDF Online

Using the AltoProtectPDF web application to protect PDFs from printing and copying brings you certain advantages:

  1. All the services are free of charge.
  2. No pop-up windows, harmful threats, annoying ads and banners.
  3. The highest level of security is provided.
  4. All documents are uploaded and processed via an encrypted connection.
  5. All the data is stored on an offsite server and deleted after the file has been processed.
  6. The storage space on your computer, smartphone or tablet always remains unused.

Password protect PDFs in seconds

Ensure that only trusted recipients are allowed to open and edit your documents. Follow the instructions below to password protect your PDFs against unauthorized access.

  • Drag and drop the file(s) you wish to protect into the box or press the ‘Choose File’ button to upload them from your device or cloud storage.
  • Once your document has been uploaded, type in a unique password and click ‘Protect File Now!’
  • Avoid number sequences and common words.
  • Click ‘Work on your PDF’ if you want to edit or email your file.
  • Click ‘Start over again’ if something went wrong and you wish to restart the process.
  • Press ‘Download Now’ to finish with your PDF and save it to your device.
  • Upload and encrypt as many files as you need (note that the file size should not exceed 25 Mb).

There are many other options available for your documents. Add annotations, use electronic signatures, erase or add text and so on. Enjoy unlimited storage space and keep your documents in one place. Invite your co-workers and business partners to work on the same document simultaneously. Contact the support team if you need any assistance.

AltoProtectPDF provides its customers with a plethora of up-to-date editing tools and is a fully functional digital workflow solution. It’s the best option if you’re looking for a way to quickly password-protect your PDF with impressive results. Try it today and join thousands of thankful users around the world!