Edit & sign

Annotate a PDF

Highlight, underline, strike through, draw and add notes.

Open in editor →Free · no sign-up · nothing uploaded

Mark up contracts, papers and drafts with a full set of annotation tools: highlighter, underline, strikethrough, freehand pen, shapes and sticky notes.

All markup flattens into the page on download so it renders the same everywhere.

How to annotate pdf

  1. 1Open the PDF in the editor.
  2. 2Pick a markup tool (highlight, underline, pen, note…).
  3. 3Mark up the page.
  4. 4Download the annotated PDF.

Why use pidief

  • ✓ Highlight, underline, strike
  • ✓ Freehand pen & shapes
  • ✓ Sticky notes
  • ✓ Everything runs in your browser — your file is never uploaded to a server.

Annotate a PDF now — free

Runs in your browser. No upload, no login, no watermark.

Open in editor →

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