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Top 5 PDF Highlighter Online Free in 2022

We are often given documents that need basic editing like adding colors, shapes, pictures, text, etc. But for a beginner, it becomes hard to find the correct tool as there are a huge number of PDF highlighting tools present digitally. These can be available across the internet and can be used from any OS device. In this article, we have written detailed sections on online PDF highlighters and an offline PDF highlighter.

These highlighters are the best source for adding different graphics and designs to your documents. The comparison between online PDF highlighters free and offline PDF highlighters will let you think and choose the best one to edit your document.

Part 1: Top 5 Online PDF Highlighters

Your teacher rejects your science project because it lacks different colors and texts that would change the outlook. What will you do in such a situation? Do you know about any efficient PDF online highlighter free that can do the job for you? Here are a few PDF text highlighters online that you can use to enhance your document:

1. PDF Bob - Online Free PDF Highlighter

PDF Bob is an online PDF highlighter free with several options to alter PDF documents, the finest of which is "Annotate PDF." This mode might help you improve your project and make it more appealing. Different shapes, like circles and rectangles, are available as annotation tools in PDF Bob. You can use a circle to create many diagrams, while a rectangle can be utilized to hold a considerable amount of data in that diagram.


  • You can use the "Highlight text" function if you want to bring your readers' attention to a particularly essential piece of information.
  • Unlike other tools, you can save the PDF file without a watermark while editing it using PDF Bob.
  • You can use the "Arrow" tool to draw attention to a certain topic


  • This tool, PDF Bob, doesn’t allow you to upload the document from any Cloud storage.

2. pdfFiller - Free Online PDF Highlighter

Have you lost track of an important document that you modified with pdfFiller and saved to your computer? Don't worry; pdfFiller is a PDF online highlighter for PDF files that saves your edited documents. It's a simple PDF highlighter with a variety of editing features for your business papers. If you're sending the document to a corporation, you can use the Highlight option of this great PDF text highlighter online to bring attention to important context components.


  • pdfFiller has a unique and vast signature feature which includes a webcam to catch the initials of your signature.
  • The Date tool has made the job easy. When you add the date in a PDF document, it looks professional and official.
  • It also provides a “Blackout” that you can use to hide any critical information inside your PDF file.


  • This PDF editor's Highlight tool will let you draw a box on the text instead of highlighting only text.

3. PDF4me - PDF Online Highligter

If you're looking for a powerful yet easy-to-use PDF online highlighter free, go no further than PDF4me. It comes with all of the capabilities you'll require for your documents. Let's assume your supervisor didn't approve the dealer's quotations; thus, you can return the document with a 'Not Approved' stamp. This can be performed by using the Stamp and Watermark tool, which includes 12 unique stamps with which you can update the status of your document.


  • If you are worried about protecting your client's sensitive information, use the 'Generate and Add QR Codes' tool to lock the secret codes.
  • PDF4me also allows you to lock any annotation after adding it properly to your PDF.
  • It has versatility in editing options. To edit a PDF file, you have to just drag and drop it.


  • You are provided with specific colors only for annotation.

4. Smallpdf - Free Online Highlighter

This is the free PDF text highlighter online that you should use to edit your documents. The interface offers powerful yet simple-to-use tools to assist you in improving your work. If you need a highlighter to highlight key aspects, Smallpdf offers two different highlighters. One is a “Text” highlighter, while the other is a “Freehand” highlighter in which you can highlight the text in any direction.


  • You can use the “Pencil” tool to add key pointers to the page and the “Eraser” to delete any undesirable annotation.
  • You can add pages and PDF files to an existing PDF document and split it into two separate PDFs by using the Split feature.
  • With this PDF highlighter online, you can select any page and change its rotation to left or right.


  • The tool doesn’t provide you with a renaming option when you download a condensed file. The file gets renamed automatically.

5. Sejda - PDF Online Highlighter

Unlike other PDF highlighters online for free, Sejda allows the users to edit the pre-existing document and make use of it by using its “OCR” feature. The “Text” tool is so helpful and has a variety of font styles, sizes, and colors; this can be used to fill out forms as well. The “Annotate” feature opens up many great options for you, like using the “Strike Out” tool to cancel or delete any false information that will negatively impact the future of your business.


  • While signing the PDF document, you can rotate the signatures in a vertical and horizontal way, as per your page’s requirement.
  • The Freehand Highlighter facilitates you by highlighting the important points on that document and not the whole text.
  • The watermark feature will help you design a watermark that secures the important information related to your work as nobody can change it.


  • Some online PDF highlighters restrict the length of PDF documents, and Sejda is one of them. It restricts it to 200 pages in length.

Part 2: Limitations of Online PDF Highlighters

PDF Online Highlighters are widely available all across the internet, and people tend to use them on a daily basis because they can be accessed from any device. But due to some limitations, there are still many people who prefer offline PDF highlighters. Some of the limitations are discussed in this section. Let’s say if your internet connection is bad, then it becomes hard for you to work online. This results in slow speed, and there becomes a high chance for you to lose track of the data.

Also, if the internet is causing a problem or is working slowly, then you won't be able to upload large files. With that, most PDF highlighters online have file size issues; you cannot upload a file larger than a specified size.

Part 3: An Offline Alternative to an Online PDF Highlighter

Offline PDF highlighters are used and preferred by most people in this digital age. Offline PDF highlighters are more versatile and easier to use as they are compatible with Mac and Windows, and you can use them without any limitations.

One of them is UPDF, a wonderful tool for all business professionals or people of any profession. This tool is completely free and without limitations. It allows you to highlight PDF with various colors and tools.

updf pdf highlighter

Once you download this PDF highlighter, you’ll instantly begin to enjoy the most delightful interface design with multiple options. To make your content look fascinating, you can add shapes of different colors like rectangles and ovals, or inseret various stikers to PDF; these will help you draw the reader’s attention.

markup pdf

The advanced interface lets you open multiple tabs and view as many PDF files as you need to in a go. With that, you can use the page layout options to adjust the page views according to the fit of your screen.

To make your content look fascinating, you can add shapes of different colors like rectangles and ovals; this will help you draw the reader’s attention. You can also fill these colored shapes with suitable text; the text can be highlighted, strikeout, and underlined as per the demand of the document.

Adding bookmarks and sticky notes to the document by using the feature will make it look more presentable, just as you do to your books in real life.

Video Tutorial on How to Highlight PDF

Wrapping Up

In this article, we have discussed both offline and online PDF highlighters that are exceptional in their own way. We have suggested five amazing PDF highlighters online for free with a number of different pros and cons. On the other hand, there is this offline PDF highlighter named UPDF that is preferred to be one of the best offline PDF tools.