PDF Annotator — Highlight, Comment & Markup PDF

Free Online PDF Annotator

Annotate any PDF directly in your browser — no account, no software install, and nothing is uploaded to any server. Upload your PDF, use the toolbar to mark it up, and download the annotated file in seconds.

Annotation Tools Available

• Freehand Draw: Draw freely with a pen in black, red, blue, green, or orange. Adjust stroke width from 1 to 8 px.
• Highlight: Drag to highlight any area in yellow, green, or pink.
• Underline / Strikethrough: Drag across text to add an underline or strikethrough.
• Text Box: Click anywhere to place a typed text annotation at that position.
• Sticky Note: Click to drop a yellow sticky note with a custom message.
• Eraser: Click near any annotation to remove it.

How to Annotate a PDF

1. Upload your PDF by dragging it onto the upload area or clicking Choose PDF.
2. Select an annotation tool from the toolbar — Draw, Highlight, Underline, Text, Sticky Note, etc.
3. Draw or click on the page to add annotations. Use Prev / Next to navigate between pages.
4. Press Ctrl+Z or the Undo button to remove the last annotation. Clear removes all annotations on the current page.
5. Click Download PDF to save the annotated file to your device.