A PDF highlighter is an essential tool for marking important information in a PDF. Whether you’re highlighting key terms in textbooks or suggesting changes to workplace documents, you don’t need expensive software to do it. QuillBot’s free online PDF editor lets you highlight text quickly and easily.
Keep reading to learn how to highlight a PDF with the best free PDF editor.
The beauty of a PDF (portable document format) file is that it can be viewed on any device using a wide range of software, so you don’t have to worry about file compatibility between Mac/Windows or desktop/mobile.
This used to come with a downside—once the PDF was written, it was very difficult (usually impossible) to write on it or annotate it.
This is no longer the case, and there are many solutions to that problem. QuillBot’s PDF editor is a quick, easy-to-use, and free tool for annotating your PDFs. And because it’s web-based, it works on any device with internet access!
Published on
August 14, 2025
by
QuillBot
Revised on
October 24, 2025
PDFs are one of the most widely used file formats in the workplace, but they’re notoriously difficult to edit without the right tools. If you’ve ever collaborated on project proposals, meeting agendas, contracts, or any type of technical writing, you’ve probably experienced challenges with how to edit a PDF or how to type on a PDF. That’s where a PDF editor comes in.
A PDF editor is a tool that allows you to modify PDFs without specialized software or advanced skills. QuillBot’s PDF editor gives you the flexibility to do more with your documents, and it’s completely free to use.