How to highlight and annotate a PDF online
Updated November 2, 2026
Reviewing a contract, studying a course or marking up a plan is easier when you can write on the document. Here is how to do it in your browser.
The tools you can use
Open your file in the PDF editor, then pick the tool that fits your note:
- "Highlight" to mark an important passage.
- "Add text" to write a comment on the page.
- "Arrow", "Line", "Rectangle" and "Circle" to point at something.
- "Freehand" to draw or circle by hand.
Make your notes easy to read
Pick one color per purpose, such as yellow for key points and red for problems. Keep comments short and put them close to what they refer to. If you make a mistake, use undo before you continue.
Sharing a marked-up PDF
When you click "Download", you get a new PDF with your marks on it, and your original file isn't changed. Give the copy a clear name, such as "contract-with-notes.pdf", so nobody confuses the two versions.