How to Highlight in Scanned PDF

July 31, 2023 2.5K views

A scanned PDF is an imaged-based PDF file, and editing it is hard. Also, with a scanned PDF, you cannot highlight its texts or add comments to it. Does this mean you cannot highlight an image in PDF completely? You can highlight scanned PDF after performing an OCR. OCR stands for optical character recognition. It is worth noting that not all PDF tools are built with an OCR functionality. Therefore, you need to get a PDF tool with an OCR tool such as PDFelement.

The best way to highlight a scanned PDF in Mac or Windows is by using a PDFelement. This PDF tool comes with an OCR technology that scans image-based PDF files and makes them editable. Once you perform OCR, you will be able to highlight and edit texts of your PDF easily. Moreover, with PDFelement, you can edit, annotate, print, OCR, create and convert PDF files all in-house.

Steps to Highlight in Scanned PDF

If you have access to an internet connection, highlighting a PDF document should be easy with online tools. Most of the tools are free – this makes them very appealing to most PDF users.

The online tool at makes highlighting PDF files extremely easy. The tool, however, limits their free service to documents up to 50 MB or 200 pages. Also, users are only allowed 3 tasks per hour when using the free service. Below, we will show you how to highlight a PDF using this online tool:


Visit on your Mac or Windows computer.



Drag and drop the document you would like to highlight. Alternatively, click the Upload PDF File button to select the document.

Note: If your PDF file is hosted online, you will need to click the dropdown arrow available to the right of the Upload PDF File button. Next, choose either Dropbox, Google Drive, OneDrive, or Web Address (URL) depending on where your document is stored.


Once the file is uploaded, click the Annotate tab. From the sub-menu that appears, select Highlight and choose the color you would like to use.


To highlight the text, simply drag the cursor over the text you would like to highlight.


Once you are done, click the Apply Changes button at the bottom of the page and then wait for the online tool to finish processing your document.


Click the Download bottom to get your highlighted PDF.

It is worth noting that most online tools have privacy issues, and once you upload your PDF document, you cannot control who can view it. For this reason, it is crucial that you only use online tools with documents that do not contain privacy issues.


If you want to know how to highlight in scanned PDF then you must get your hands on the best software. It will not only get you the desired result but will also ensure that you enjoy other features as well. To highlight scanned PDFs many programs are available online to get the work done. The issue is that the data is not safe and secure with these programs. WPS office is the best and the state of art program that will make highlighting possible for you with perfection and ease.

15 years of office industry experience, tech lover and copywriter. Follow me for product reviews, comparisons, and recommendations for new apps and software.