How to Annotate a PDF on Mac (Free, Multiple Methods)
Add comments, highlights, and notes to a PDF on Mac using Preview or browser tools — no Adobe Acrobat required.
Mac offers strong built-in annotation through Preview — highlights, comments, shapes, and text. For more structured annotation, FixMyPDF's comment tool adds a browser-based option in Safari with a clean workflow for adding and positioning notes.
Method 1: Preview (Built-In, Comprehensive)
Open the PDF in Preview. Click the Markup Toolbar button (pencil icon). Tools available: Highlight (select text then click Highlight), Add Note (yellow sticky note), Text tool (click to add a text box), Shapes (rectangles, circles, arrows). All annotations are saved when you press ⌘S.
Keyboard Shortcuts for Preview Annotations
In Preview's Markup Toolbar: ⌃⌘H highlights selected text; ⌃⌘N adds a note; ⌃⌘T adds a text box. Hold ⌘ while drawing a shape to snap to regular proportions. These shortcuts speed up annotation of multi-page documents significantly.
Method 2: FixMyPDF Add Comments Tool
Go to fixmypdf.in/tools/add-comments in Safari or Chrome. Upload your PDF, click to add comment boxes at any position on the page, type your note, and download the annotated PDF. Good for clean comment-box annotations without the full Preview toolbar.
Annotations in Chrome vs Preview
Chrome's built-in PDF viewer (open any PDF in Chrome) supports basic highlighting and comments via the Edit menu. It's less featured than Preview but useful for quick annotations without opening another app. Annotations saved in Chrome are compatible with Acrobat and other readers.
Flattening Annotations Before Sharing
By default, PDF annotations are a separate layer that some readers display differently or hide. To ensure your highlights and comments are visible to all recipients regardless of their PDF reader, use our flatten PDF tool to merge annotations into the page content before sharing.
Commenting on PDFs for Academic Review on Mac
For academic and professional review workflows — marking up a paper, reviewing a proposal, annotating student work — Preview's full annotation suite is the most efficient on Mac. Add highlights for key passages, sticky note comments for questions, and use the shape tools to draw attention to specific figures.
After Annotating
Once annotated, you can compress the PDF (annotations add file size), password-protect it before distributing to reviewers, or use our flatten tool to make the annotations permanent and visible in all PDF viewers.
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