Annotate PDF (Free, Private, No Upload)

PDF annotation enables collaborative review, document markup, and visual feedback without modifying the original content. This tool adds highlights, comments, shapes, and drawings directly within your browser, making it perfect for reviewing legal documents, marking up design mockups, providing feedback on research papers, or collaborating on contracts. Because everything happens locally on your device, sensitive information in confidential agreements, proprietary designs, financial reports, or personal documents never leaves your computer. This privacy-preserving architecture is essential when working with documents containing trade secrets, attorney-client privileged information, or regulated data that cannot be uploaded to third-party services. The annotation tools include text highlighting in multiple colors for categorizing content, comment bubbles for detailed feedback, shapes like rectangles and circles for emphasizing areas, arrows for directing attention, and freehand drawing for custom markup. Unlike simple image annotation tools, this PDF annotator preserves the document structure and embeds annotations directly into the PDF file, ensuring they display correctly in any PDF reader. Annotations are saved as part of the PDF itself, not as separate files, maintaining document integrity and preventing annotation loss. The tool supports multi-page documents with page-by-page navigation, allowing systematic review of lengthy contracts, reports, or manuscripts. Color-coded highlights help organize feedback by priority or category—use yellow for minor suggestions, red for critical issues, and green for approved sections. Comment annotations provide space for detailed explanations, questions, or clarifications that simple highlights cannot convey. Shape tools quickly draw attention to specific areas, tables, or figures that need discussion. The freehand drawing tool enables custom diagrams, arrows, or circles around problematic areas. All annotations sync across pages, and you can clear annotations per page or save the entire marked-up document. This comprehensive annotation suite rivals expensive desktop PDF editors while maintaining complete privacy and requiring no software installation.

  1. Click Choose PDF or drag your file onto the drop zone.
  2. Select an annotation tool: highlight, comment, rectangle, circle, arrow, freehand draw, or text.
  3. Choose your preferred color (yellow, green, red, or blue).
  4. Click and drag on the PDF to add annotations.
  5. Navigate between pages using the arrow buttons to annotate multiple pages.
  6. Click Save Annotated PDF to download your marked-up document.

Related tools: Redact PDF, Sign PDF, Stamp PDF

FAQ

Are annotations permanent?

Yes, annotations are embedded directly into the PDF file when you save. They will appear in any PDF reader that supports standard PDF annotations. However, some readers allow editing or removing annotations, so they're not tamper-proof like flattened redactions.

Can I edit annotations after adding them?

Currently, once an annotation is added, you cannot individually edit it in this tool. You can clear all annotations on a page and re-add them, or use the undo functionality before saving. For advanced annotation editing, consider desktop PDF software.

What's the difference between annotations and stamps?

Annotations are interactive elements that can be commented on, replied to, and often toggled on/off in PDF readers. Stamps are static images or text permanently placed on pages. Use annotations for collaborative review and feedback; use stamps for official markings, approvals, or branding.

Will my annotations appear in all PDF readers?

Most modern PDF readers support standard PDF annotations, including Adobe Acrobat, Preview on Mac, Foxit Reader, and browser-based PDF viewers. However, some basic or older readers may not display annotations correctly. For maximum compatibility, consider flattening annotations or using stamps instead.

Can I collaborate with others using these annotations?

Yes, once you save the annotated PDF, you can share it with others. Recipients can view your annotations in any compatible PDF reader and add their own annotations using their PDF software. Each annotator's markup typically shows their name (if configured in their PDF reader), enabling multi-person document review workflows.