How to add comments and notes to a PDF

The fastest way: drop a sticky note

A sticky note is the cleanest way to comment on a document you're reviewing for someone else. It sits on top of the page without changing the original text, so your feedback is obvious and the author's content stays untouched.

This is the right tool when your comment is about a spot on the page — a paragraph, a figure, a number — rather than a single word you want to rewrite.

• Open the PDF in the editor (drag and drop or pick the file).
• Choose the sticky note tool and click where the comment belongs.
• Type your remark, then drag the note to fine-tune its position.
• Repeat for each point, then download. The notes are saved into the file.

Inline feedback: highlight, then add a text comment

When your comment is tied to a specific sentence or clause, point at it first. Drag the highlighter across the passage so the author knows exactly what you mean, then add a short text comment in the margin beside it.

The result is easy for the author to follow: the flagged text and your note sit right next to each other, so your reasoning is clear without you ever editing their words.

• Select the highlight tool and drag across the words you're commenting on.
• Switch to the add-text tool and click in the nearby margin.
• Type your note — the text auto-matches the size and color of nearby text so it reads cleanly.
• Use the shapes or line tool if you want to draw an arrow from your note to the passage.

Sticky note vs. inline text: which to use

You can mix all of these in one pass. Every comment, highlight, and note is movable and deletable, and undo/redo is always available, so it's easy to clean up before you send the file back.

• Use a sticky note for general remarks, questions, or feedback on a whole section or image.
• Use highlight + margin text when you're reacting to specific wording and want to point right at it.
• Use a line or freehand draw to connect a comment to the exact spot it refers to.
• Keep notes short. If you have a lot to say, number your sticky notes and write the detail in a separate message.

Why review it locally instead of uploading

Documents that go out for review are often contracts, drafts, financials, or anything else not meant for public servers. A browser editor that runs locally keeps the file on your device the whole time — nothing is uploaded to a server to be processed or stored.

It's also free with no signup and no watermark, so the PDF you send back looks exactly like the one you received, just with your comments added. When you're done, download the marked-up copy and share it however you normally would.