How to Annotate a PDF Online

Annotating a PDF lets you comment without changing the original layout. Highlight the important lines, add a note, draw an arrow, and send it back.

What annotation is good for

Reviewing a contract, marking up a draft, leaving feedback on a design, or flagging the figures that matter. Annotations sit on top of the page, so the underlying document stays intact and readable.

How to annotate a PDF

  1. Open the PDF Annotator.
  2. Add your PDF.
  3. Use the highlight, text, and drawing tools to mark up the pages.
  4. Download the annotated file.

Your document is processed in the browser, so private files are never uploaded.

Annotation tips

  • Highlight sparingly. A page covered in yellow is as hard to read as no marks at all.
  • Use short text notes for specific requests rather than long paragraphs.
  • Arrows and boxes are great for pointing at a figure or a clause.

Related tasks

If you need to sign rather than comment, use Sign PDF. To fill in form fields, try the Fillable PDF Creator.

Frequently asked questions

Can I highlight text in a PDF for free?

Yes. The PDF Annotator lets you highlight, add notes, and draw, then download the marked-up file at no cost.

Will annotations change the original document?

No. Annotations sit on top of the page, so the underlying content stays the same.

Is my PDF uploaded when I annotate it?

No. Annotation happens in your browser, so the file stays private.

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