January 6, 2025 Editing 7 min read By Horizin Team Last updated: September 24, 2025

Annotate a PDF Online: Highlight, Comment, and Draw

Mark up PDFs clearly with highlights, notes, and shapes—perfect for reviews, classrooms, and teams.

Annotate a PDF feature image

Core Annotation Tools

  • Highlight: Emphasize key text; use multiple colors for categories.
  • Comment: Add notes with usernames for clarity.
  • Draw: Freehand circles/arrows to point out issues.
  • Shapes: Boxes and lines for neat callouts.

Step-by-Step

  1. Open the PDF Editor.
  2. Select Highlight/Comment/Draw as needed.
  3. Use consistent colors and labels; save regularly.

Collaboration Tips

  • Use color conventions per reviewer.
  • Resolve comments after addressing feedback.
  • Export a "clean" copy with comments removed for final delivery.

Conclusion

Clear annotations lead to faster decisions. Keep notes concise, use consistent styles, and archive a reviewed copy.

FAQs

Can I export comments?

Yes—export to a summary or keep them in a separate annotated PDF.

Do highlights print?

Yes—ensure print settings include markup if you want them in printouts.