Add notes, highlights & stamps to your PDF — click anywhere on a page to annotate
Annotations are baked into the PDF as visual overlays (text, rectangles, stamps). Existing embedded annotations in the source PDF are not editable. All processing happens in your browser — your file never leaves your device.
About this tool
Mark up PDFs with notes, highlights and stamps. No printout, no upload, free.
What Is PDF Annotator?
PDF Annotator is a free browser-based markup tool that lets you add highlights, sticky notes, text stamps, arrows, and freehand drawings directly onto any PDF. All annotations are rendered as vector overlays using the Canvas API — nothing is uploaded to a server. You can choose from 8 highlight colors, adjust opacity, place resizable sticky notes with custom text, and stamp pages with "Approved", "Rejected", "Confidential", or "Draft" labels. The annotated PDF exports as a new file with annotations flattened into the page, ready to email or archive.
Who Should Use PDF Annotator?
Teachers use this tool to mark up student submissions with corrections and feedback without printing. Project managers stamp "Approved" on design proofs and share them instantly. Legal reviewers highlight key clauses and attach notes for colleagues. Real estate agents circle items on inspection reports. HR teams annotate policy documents during review cycles. Freelancers mark up client mockups with revision requests. Because everything runs locally, it is ideal for sensitive documents — medical records, financial statements, privileged legal correspondence — where uploading to a cloud annotator would violate policy.
How to Use PDF Annotator
Open your PDF by clicking "Choose File" or dragging it onto the drop zone. The document renders page by page in the viewer. Select a tool from the toolbar: highlighter (pick a color and drag over text), sticky note (click to place, type your note), stamp (choose a label and click where to apply), or pen (freehand draw). Annotations appear instantly. Navigate pages with the arrows. When finished, click "Export PDF" to download a new file with all annotations baked in. The original file is never modified. Close the tab and all data is gone.
Frequently asked
What annotation types can I add to a PDF?
You can add sticky notes, text highlights in 5 colors, freehand drawings, stamps (Approved, Rejected, Confidential), and typed text boxes. Annotations are embedded into the PDF layer so they display correctly in Adobe Reader, Preview, and any PDF viewer without requiring special software.
Can I annotate for a team review workflow?
Yes. Add color-coded highlights and comments for each reviewer, then export the annotated PDF to share. Because annotation runs entirely in your browser, sensitive documents like NDAs or merger agreements never leave your device—no cloud storage or third-party server access required.
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