AmigoPDF
Step-by-step guide

How to highlight a PDF online

Studying a contract, marking a lease, or annotating notes? You can drag highlights onto any PDF in your browser and download the marked-up copy — free, no account, nothing uploaded.

What you need

Just a web browser and your PDF. Everything happens on your device.

Highlight a PDF in 5 steps

  1. Open your PDF

    Go to the PDF editor and open your file (click Open PDF or drag it in).

  2. Choose the Highlight tool

    Select Highlight in the toolbar (or press H).

  3. Drag across the passage

    Click and drag over the text you want to mark. Release, and the highlight is placed.

  4. Pick color and opacity

    Use the panel to switch colors (yellow, or any color you like) and adjust how strong the highlight is.

  5. Export the marked-up PDF

    Click Export to download a copy with your highlights baked in.

Tip: the text stays readable

Highlights use a “multiply” blend — like a real highlighter, the words underneath stay crisp. Use different colors for different topics.

Highlight your PDF now

Free, private, and works on desktop and mobile.

Open the editor

Frequently asked questions

Can I remove or move a highlight?

Yes — switch to the Select tool, click the highlight, then drag it or delete it.

Does highlighting change my original file?

No. You download a new marked-up copy; the original stays untouched.

Can I highlight in different colors?

Yes — pick any color and opacity in the properties panel.

Can I highlight on my phone?

Yes — drag with your finger, same as on desktop.

This guide is for general information. AmigoPDF is a free, in-browser utility; always keep a copy of your original files.