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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. Processing happens in this browser tab; BrowserPDF has no file-processing backend or file-upload endpoint.

Drag your PDF file here

or choose from your computer

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.
  • No file-upload endpoint. Document processing happens in this browser tab. BrowserPDF has no file-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?

Highlight rectangles are drawn into the PDF in this browser tab; BrowserPDF has no file-upload endpoint.