Edit PDF · 2 min read

How to Add a Comment to a PDF — Free Online

Adding review comments to PDFs — for feedback, corrections, or collaboration — is straightforward with the annotation tools in PDF Studio.

1

Open pdfeditor.onl/pdf-studio

Navigate to PDF Studio and upload your PDF.

2

Add Text Annotations

Select the Text tool. Click any location on the page to place a text annotation. Type your comment. Use a colored text or bordered box style to make comments stand out from the document text.

Tip: Use a bright color (blue, red, or green) for comment text boxes to visually distinguish them from the original document content.

3

Download the Commented PDF

Click Download PDF. All comments are permanently embedded and visible when the file is opened by the recipient.

Add Comments to PDF — Free →

Frequently Asked Questions

Can recipients reply to comments in the downloaded PDF?

Comments embedded with this method are flattened text annotations — recipients can see them but cannot reply in the file. For threaded comments, use Adobe Acrobat's review features.

Is this free?

Yes — completely free at pdfeditor.onl/pdf-studio.

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