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How to Annotate a PDF — Add Notes & Comments Free Online | PDF AI Work Blog

PDF AI Work Team·July 29, 2026

Add comments, sticky notes, and annotations to any PDF with the Annotate PDF tool. Perfect for document review, feedback, and collaborative editing.

Annotation Types

  • Sticky notes: Click anywhere to add a comment bubble
  • Text comments: Inline annotations that appear in the margin
  • Callouts: Arrows pointing to specific content with notes
  1. Open Edit PDF
  2. Upload your PDF
  3. Use the annotation tools to add notes and comments
  4. Annotations appear as standard PDF comments
  5. Download — recipients can view comments in any PDF reader

Combine with Highlight PDF for comprehensive markup, or Sign PDF to add your approval.

Free, no signup. Annotate your PDF now.

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