Annotate PDF
Add highlights, drawings, shapes, and notes to PDFs for free. No upload — all processing in your browser.
Your files never leave your device. All processing happens in your browser. We don't upload, store, or access your files.
Drop your PDF here or click to browse
PDF files — no size limit
How to Use
- 1Drop your PDF file into the upload area or click to browse
- 2Select an annotation tool from the toolbar: highlight, draw, sticky note, rectangle, circle, arrow, or line
- 3Click and drag on the PDF page to place annotations. Adjust color, opacity, and stroke width as needed.
- 4Click "Apply Annotations & Download" to save the annotated PDF
Need more detail? Read our complete guide.
About This Tool
Mark up PDF documents with highlights, freehand drawings, sticky notes, rectangles, circles, arrows, and lines using our free online annotation tool. Choose from multiple colors, adjust opacity and stroke width, and navigate multi-page documents with ease. Every annotation is rendered directly onto the PDF pages. All processing happens 100% in your browser — your files are never uploaded to any server, making this the most private way to annotate PDFs online.
Frequently Asked Questions
How does the PDF annotation tool work?
Select an annotation tool from the toolbar — highlight, freehand draw, sticky note, rectangle, circle, arrow, or line. Then click and drag on the PDF page to place your annotation. Adjust color, opacity, and stroke width in the settings panel. When you are done, click "Apply Annotations & Download" to save the annotated PDF. All processing happens in your browser.
What types of annotations can I add?
You can add seven types of annotations: highlights (semi-transparent colored rectangles), freehand drawings (pen tool), sticky notes (text boxes), rectangles (outlines), circles/ellipses (outlines), arrows, and lines. Each type supports custom colors, opacity, and stroke width.
Are my annotations permanent?
Yes. When you apply annotations and download the result, all annotations are drawn directly onto the PDF pages. They become part of the document content and cannot be removed from the annotated file. Always keep a copy of your original document.
Are my files uploaded to a server?
No. All annotation processing happens entirely in your browser using JavaScript. Your PDF file is never transmitted over the network. You can verify this by disconnecting from the internet after loading the page — the tool continues to work.