PDF Annotation Tool
Annotate PDF files online for free with highlights, comments, drawings, and simple shapes. Review documents right in your browser, then save the marked-up PDF instantly.
Annotate in Your Browser
Upload a PDF to start highlighting, adding comments, drawing shapes, and marking up pages directly on screen.
How to use
Upload your PDF
Select a file from your device. The annotation workspace loads the PDF right in your browser.
Annotate with the toolbar
Use highlight, comment, draw, or shapes to mark important content, add review notes, and guide collaborators.
Save and download
When your annotations look right, export the updated PDF instantly without installing extra software.
What is PDF annotation?
PDF annotation is the process of adding visual notes and markup to a PDF without rewriting the original document. Highlights, comments, drawings, and shapes make it easier to review files, explain changes, and call attention to important sections.
How to annotate PDF files
Upload the PDF, choose an annotation tool, then click or drag directly on the page preview. This workflow works well for quick feedback rounds, document review, and study notes because you can mark the PDF while keeping the original layout intact.
Uses in study, work, and collaboration
Students often annotate PDFs to highlight passages and add margin notes. Teams use PDF markups to review contracts, design proofs, project documents, and client deliverables. In collaborative settings, annotations help people give precise feedback without changing the source file itself.
Types of annotations
- Highlights for important phrases, paragraphs, and action items.
- Comments for review notes, reminders, and feedback.
- Freehand drawing for circling issues or sketching callouts.
- Shapes for boxes, review marks, and visual emphasis.
Features
Highlight text
Mark key sections and important passages with quick visual emphasis.
Add comments
Place comment notes directly on the page for review, study, or collaboration.
Draw shapes
Use boxes and other simple shapes to frame issues, call out sections, or organize visual feedback.
Mobile responsive
Annotate PDFs from desktop or mobile browsers without installing a dedicated app.
Advanced feature ideas
- Sticky notes for richer review comments and reminder-style markup.
- Collaboration mode for shared review workflows.
- Export annotations only for compact markup handoff.
- Layer visibility toggle for advanced annotation control.
FAQ
How do I annotate a PDF?
Upload your PDF and use annotation tools.
Is this tool free?
Yes.
Can I highlight text?
Yes.
Can I add comments?
Yes.