Annotate PDF Online, Free

Mark up any PDF with sticky notes, shapes, arrows, and freehand ink. Perfect for reviewing contracts, proofing designs, or giving feedback on reports.

Annotate a PDF

Why Konomic

Full annotation toolkit

Sticky notes, text boxes, rectangles, ellipses, arrows, lines, and a freehand pen — all in one toolbar.

Review-friendly

Each annotation is a separate layer you can move, resize, or delete without touching the underlying PDF.

Share the result

Download the annotated PDF and email it — annotations render in any PDF reader including Acrobat and Preview.

Free forever

Unlimited annotations on the free plan. No watermark, no hidden export fee.

How it works

  1. 1Upload the PDF you want to annotate
  2. 2Pick a tool: sticky note, shape, arrow, or pen
  3. 3Click on the page to place your annotation
  4. 4Download the annotated PDF

Frequently asked questions

Will my annotations show in Adobe Acrobat?

Yes. Konomic exports standard PDF annotation objects that render correctly in Acrobat, Preview, Foxit, and every major PDF reader.

Can I delete an annotation later?

Yes. Each annotation is editable until you flatten the file. Open the PDF in Konomic again to move or remove marks.

Can I annotate on mobile?

Yes. The pen and sticky-note tools work on touchscreens. A stylus gives the smoothest lines.

Does annotating change the original text?

No. Annotations sit on a separate layer above the PDF content — the underlying document is untouched.

Is it really free?

Yes. Unlimited annotations on the free plan with no watermark and no signup.