PDF Highlighter — Highlight & Annotate PDFs in Chrome

With Web Highlights, you can highlight text and add notes on any PDF — whether it's hosted online or stored locally on your computer. No separate PDF software needed; everything works right inside your Chrome browser.

Prerequisites

Before we begin, make sure you have our browser extension installed. You can install it here or get it from the Chrome Web Store, Firefox Add-ons, or Microsoft Edge Add-ons.

How to Highlight a PDF in Chrome

Highlighting a PDF with Web Highlights works the same way as highlighting any webpage:

1. Open a PDF in Chrome — Navigate to any online PDF, or drag a local PDF file into Chrome
2. Web Highlights automatically detects the PDF and opens it in our built-in PDF viewer
3. Select any text in the PDF — the highlighter popup appears
4. Click the highlight color to save your highlight
5. Add notes by clicking the note icon on any highlight

Your PDF highlights are automatically saved and will reappear whenever you open the same PDF again.

How to Annotate a PDF

Beyond simple highlighting, Web Highlights lets you annotate PDFs with rich notes:

• Add notes to any highlight — Click a highlight to open the note editor and add your thoughts
• Use multiple highlight colors — Color-code your annotations to categorize information (e.g., key points, questions, definitions). Learn more about multiple color highlighting.
• Tag your highlights — Organize PDF annotations with custom tags for easy retrieval
• Export annotations — Export your PDF highlights and notes to Markdown, HTML, PDF, Notion, or Capacities

Opening PDFs

Online PDFs

Simply navigate to any PDF URL in Chrome. Web Highlights will automatically detect it and offer to open it in our PDF viewer.

Local PDFs

To highlight a local PDF file:

1. Drag the PDF file into a Chrome browser tab, or
2. Right-click the PDF file → Open with → Chrome

Web Highlights will transform the PDF into a highlightable format in our built-in viewer.

Organize Your PDF Research

Once you've highlighted a PDF, you can organize your annotations just like any other page in Web Highlights:

• Add tags to group PDFs by topic, project, or priority
• Take notes on individual highlights to add your own context
• Share your annotations with a public link so others can see your highlights
• Export to Notion or Markdown to integrate PDF research into your workflow

Read More

You can find a detailed walkthrough with screenshots in our blog post:

For a comparison of PDF highlighter tools, see our blog post on the best PDF web highlighter Chrome extensions.

PDF Highlighting Limitations

PDF files always need to be opened in our PDF viewer. Web Highlights will transform those PDFs into a format that can be highlighted. Please note that for larger PDFs, this might take a while.

Also, currently, PDF highlighting has the following limitations:

• You cannot highlight images in PDFs
• Highlights in local PDF files can only be recreated if the PDF file is available on the same device at the same location

Common Questions

Can I highlight any PDF in Chrome?

Yes — Web Highlights works with most PDFs that contain selectable text. Scanned PDFs (image-based) without an OCR text layer cannot be highlighted, as there is no selectable text.

Do my PDF highlights sync across devices?

Yes! All your highlights are stored in the cloud and accessible from any device through the web app. For local PDFs, the file must be at the same path on each device.

Can I export my PDF annotations?

Yes. You can export highlights and notes from any PDF to Markdown, HTML, PDF, Notion, or Capacities using the export menu in the sidebar.

Is Web Highlights free as a PDF highlighter?

Web Highlights offers a free tier that includes PDF highlighting. For advanced features like unlimited highlights and more storage, check our pricing page.