Annotate PDF
Highlight, underline, draw and add sticky notes to a PDF.
or drop files here
Runs on your device — your files are not uploaded.
Free: files up to 200 MB, up to 50 files. No daily limit.
To annotate a PDF, open it in Annotate PDF and use the toolbar to add notes, highlights, arrows, shapes or freehand drawings on the page, then save.
How to annotate a PDF in 3 steps
- 1
Choose a PDF file.
- 2
Choose Annotate, then drag across text to highlight it or click to add a note.
- 3
Select Save, then download your PDF.
What can Annotate PDF do?
- Runs in your browser: your file never leaves your device.
- The full editor is one click away: change existing text, add images, shapes, links, notes and signatures.
- Undo and redo every step, and come back to unsaved edits within 2 hours.
- Works on phones with a bottom toolbar and pinch to zoom.
How do I annotate a PDF online?
To annotate a PDF, pick a tool in the toolbar and mark up the page: highlight text, add sticky notes, draw freehand or place shapes and arrows. Select any mark later to move it, change its colour or delete it.
Which markup tools can I use?
- Text markup: highlight, underline, strike out and squiggly underline, each with an optional comment.
- Comments: sticky notes and text callouts.
- Drawing: a freehand pen with colour, width and opacity.
- Shapes: rectangles, ellipses, lines and arrows.
- Stamps: Approved, Rejected, Draft, Confidential and more.
Can other people see my comments?
Yes, annotations are standard PDF annotations, so anyone who opens the file in a PDF reader sees them. To delete them later, use Remove annotations. To make them part of the page so they can't be changed, use Flatten PDF.
This page opens the PDFDaily editor with the right tool already selected, and every other editing tool in Edit PDF is one click away.
Frequently asked questions
How do I comment on a PDF?
Choose a sticky note, click where the comment should go and type it. Highlights, underlines and strikeouts can carry a comment too.
Can I draw on a PDF?
Yes. Choose Draw and use the mouse, a pen or one finger, with your own pen colour, width and opacity. Rectangles, ellipses, lines and arrows are there for neater markup.
What markup tools does the PDF annotator have?
Highlight, underline, strike out and squiggly underline, sticky notes, text callouts, freehand drawing, shapes, arrows and stamps such as Approved or Draft.
Do annotations work in Adobe Reader and other apps?
Yes. Notes, highlights, drawings, shapes and stamps are saved as standard PDF annotations, so Adobe Reader, Preview and web browsers show them.
Is it free to annotate a PDF?
Yes. Annotating runs on your device, so there is no daily limit.
Are my files uploaded when I annotate?
No. The PDF is opened and saved in your browser.
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Last updated October 23, 2026