How to highlight text in a PDF

To highlight text in a PDF, open the file at pdfviewer.work, click Highlight, choose a color and drag across the words you want to mark. Click Download and the highlights are written into a new copy of the PDF. The file stays in your browser tab the whole time, so nothing is uploaded.

Highlight text in a PDF in four steps

1. Open the PDF. Drop the file onto this page, or click Open a PDF and pick it from your computer. The same drop zone is on the highlight tool page and the home page.
2. Click Highlight in the toolbar and choose a color. Yellow is what most people reach for; green, blue, red, orange, purple and black are there if you color-code.
3. Drag across the text. Release the mouse and the mark stays on the page. Repeat for every passage, switching colors between them if you like.
4. Click Download. The viewer writes a new PDF with the highlights embedded. Your original file on disk is untouched, so a clean copy is always one click away.

Made a mess? Press Ctrl+Z (Cmd+Z on a Mac) to undo the last highlight, or pick Eraser and click a single highlight to remove just that one.

Picking colors that mean something

Color-coding only helps when each color has a job. A scheme that works for study notes and contract review alike: yellow for key facts, green for definitions and names, blue for anything you plan to quote, red for claims you must verify or disagree with. Orange and purple are spare colors for a second reader, and black gives you a solid bar when a tint is not enough.

A highlight sits over the page content, so passages printed on a dark banner or in colored boxes can end up hard to read. For those spots a short note in the margin from the Text tool is clearer than a highlight. If you need to point at a diagram rather than words, the Draw tool lets you circle it freehand.

How to highlight a PDF on Mac, Windows, iPad or Chromebook

The browser steps above are identical on every system, which is the point of a browser tool. If you would rather use something already installed:

• Mac: Preview opens every PDF. Click the Markup toolbar button, then the highlighter, and drag over text; save with Cmd+S. The PDF Viewer vs Preview page lists where each one is stronger.
• Windows: Microsoft Edge has a highlighter in its PDF toolbar, and the free Adobe Acrobat Reader has one under Comment. Chrome's built-in viewer has few annotation tools, so for highlighting open the file at pdfviewer.work, or let the Chrome extension send web PDFs straight into the viewer.
• iPad and iPhone: Markup in the Files app can highlight, and so can the viewer in Safari. There is a separate walkthrough for annotating a PDF on iPad.
• Chromebook: the viewer in Chrome is the simplest route because nothing needs installing.

Highlighting for study, contract review and team feedback

For a textbook chapter, highlight on the first read and then use Ctrl+F to jump between the terms you marked; the search box steps through next and previous matches, so a highlighted definition is never more than a keystroke away. Keep the thumbnail sidebar open to see which pages carry marks and which you skipped.

For a contract, pair each highlight with a short note from the Text tool: "check date", "ask legal". A reviewer gets the color for the where and the note for the why. When the file goes back, the other side sees your marks in their own reader, because Download writes them into the PDF itself rather than into a side file.

For a printed handout, click Print after highlighting; the browser's print dialog opens with the page as you see it. Highlighting a scan works the same way, with one difference: the marks sit over an image, so a later OCR pass is what makes the words under them searchable.

Troubleshooting: the highlight does not save or the file will not open

• The PDF is a scan. A scanned page is a picture, so there are no words underneath for Search to find. You can still mark passages, but if you need Ctrl+F to work afterwards, run OCR first.
• The file asks for a password. The viewer cannot open a PDF that needs a password to open. Remove the password first (the password guide explains how). A file that opens but blocks editing can be freed with Remove Restrictions.
• Highlights vanished after closing the tab. Edits live in the tab until you click Download. Closing the tab discards them, by design, because nothing is stored anywhere.
• The recipient sees no highlights. Send the downloaded copy, not the original. Nothing is written back into the file you opened.

Frequently asked questions