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Highlight, underline, or strikethrough text in your PDF documents.
Your file stays completely private. All annotation happens locally — no uploads, no servers. Drag to draw highlights, underlines, or strikethroughs over text, then download the annotated PDF.
Free users limited to 10MB & 5s wait. Upgrade for 100MB & no limits
Add highlights, underlines, and strikethroughs to your PDF documents. Select an annotation mode, then click and drag over any text to mark it up. All annotations are drawn as colored rectangles and lines — perfect for studying, reviewing documents, or marking up drafts.
Perfect for: highlighting key passages in research papers, underlining important clauses in contracts, strikethrough text in drafts, and reviewing PDF documents with visual annotations.
All processing happens locally in your browser — no uploads, no servers, complete privacy. Keywords: annotate PDF online free, highlight PDF, underline PDF, strikethrough PDF, PDF annotation tool.