Nitro PDF annotator

Annotate and Highlight PDF Files

With access to the full-featured PDF annotator in Nitro Pro, you can easily provide trackable comments and feedback for seamless collaboration on any project.

Mark up and annotate PDF documents

The PDF annotator in Nitro Pro equips you with powerful tools to highlight and add comments to PDF files. Your comments will be universally compatible with any PDF program regardless of if your viewer is working in Nitro Pro, Acrobat, or another solution.

Track comments and feedback

Reviewers can reply directly to colleagues’ notes for effortless collaboration, and every comment will be attributed to the corresponding author for easy-to-follow conversations. To further organize comments, you can combine all notes into a single PDF file.

Compare PDF files

Instead of poring over side-by-side PDFs, you can use Nitro Pro to quickly spot any text or image differences between two versions of a file.

Stamp documents

Whether you need to mark a document “Paid,” “Approved,” or “Copy,” Nitro Pro can digitally stamp your PDF file just as you would with a rubber stamp. Use our palette of ready‐made stamps, create your own, or choose a custom image for bespoke flair.

Take measurements

Measure distance, perimeter, and area within PDF blueprints, drawings, and computer‐aided design (CAD) files before sending them to the printer.