Highlight PDF
Draw semi-transparent colored highlights over text in your PDF, like a real highlighter pen. Pick the color and opacity, mark up every page you need, then download. Nothing runs on a server, nothing is uploaded.
Drag your PDF file here
or choose from your computer
Preparing…
How it works
- Semi-transparent rectangles. Each highlight you draw is burned into the page as a colored, semi-transparent fill with pdf-lib, so the text underneath stays visible through the color, just like a real highlighter pen.
- Color and opacity. Pick from yellow, green, blue, pink, or orange, and set the opacity from 20% to 80%. The current color and opacity are used for every highlight when the file is saved.
- Nothing is uploaded. Everything happens in this browser tab. There is no upload endpoint.
Frequently asked questions
Can I highlight text on more than one page?
Yes. Pick a page from the thumbnail grid, click and drag to highlight, then pick another page and keep going. Every highlight is saved together and applied to the final PDF in one pass.
Can I change the highlight color and opacity?
Yes. Choose from yellow, green, blue, pink, or orange, and set the opacity anywhere from 20% to 80%. The current color and opacity are used for new highlights and when the PDF is saved.
Is my PDF uploaded anywhere?
Never. The highlight rectangles are drawn into the PDF entirely on your device, like everything else on this site.