How to add comments to a PDF
Quick answer: To add comments to a PDF, open it in a PDF editor, choose the Comment tool, tap the spot on the page you want to talk about, and type your note. In Quick PDF this places a sticky-note comment on the page, and the comments are saved in the PDF when you download or share it.
Sign in with Google or email and start editing. Saving your file starts a free trial: 7 days on yearly ($29.78/yr) or 2 days on monthly ($2.99/mo). Cancel anytime. 🔒 Your file stays on your device.
Comments let you give feedback on a document without changing its wording: a question on a contract, a correction on a draft flyer, a note to yourself on a study PDF. Instead of writing a long email that says “on page 4, third paragraph…”, you put the note exactly where it belongs.
Below you will find the steps in Quick PDF, which works in the browser on iPhone, Android, Mac, Windows and Chromebook, plus how to write comments people actually act on and what to check before you send the file back.
Add comments to a PDF with Quick PDF
- Open your PDF Visit quickpdfapp.com, sign in, and open the PDF from your Files app, Downloads folder or desktop. It opens inside your browser on your device.
- Choose Comment Tap or click Comment in the editor toolbar.
- Tap where the note belongs Tap the exact spot on the page your note is about, such as the start of a paragraph or next to a number. A sticky-note comment appears there.
- Type your comment Write the note. Keep it to one point per comment so each one is easy to answer.
- Point at the detail If the note needs extra context, use Highlight to mark the exact words or Shapes to add an arrow or box next to it.
- Save and send Tap Download to save a copy with your comments, or Share to send it by Mail, Messages, WhatsApp or another app on your phone.
Comments, highlights, drawings or text: which should you use?
Quick PDF has several ways to mark up a page. Each one suits a different job:
| Tool | Best for |
|---|---|
| Comment | A question, explanation or request that needs words |
| Highlight | Marking the exact text a note is about |
| Draw and Shapes | Circling, underlining, arrows and boxes |
| Add text | Words that should print as part of the page |
Use Comment for conversation and Add text for content. If you are filling in a form, typed text is what you want; a sticky note would look like a remark about the form rather than an answer on it.
How to write PDF comments people act on
Good comments save a round of back-and-forth. A few habits help:
- One point per note. Three issues in one comment usually means one gets missed.
- Say what you want. “Change the date to March 3” is clearer than “date?”.
- Place it next to the problem. Tap right beside the word or figure rather than in the margin of a different paragraph.
- Mark the words too. A quick highlight under the sentence shows exactly what the note means.
- Add your initials if several people are reviewing the same file, so everyone knows who asked what.
Commenting on a PDF from your phone
Reviewing on a phone is common when a document arrives by email or text and you need to reply quickly.
- iPhone: save the attachment to Files (tap it, tap the share icon, then Save to Files), then open quickpdfapp.com in Safari and pick the file.
- Android: open or download the attachment so it lands in Downloads, then open quickpdfapp.com in Chrome and pick it from there.
Zoom in before you tap so the note lands in the right spot. When you are done, use Share instead of Download to send the file straight back through Mail or WhatsApp without hunting for it in your folders.
Other ways to comment on a PDF
- Mac Preview can add notes to a PDF from its Markup toolbar.
- Microsoft Edge on Windows can add notes to text in PDFs it opens.
- Shared online documents such as Google Docs are better when several people need to discuss and reply to each other in real time. Quick PDF does not do live collaboration: you add your comments, then send the file.
Quick PDF is a good fit when you want one tool that works the same on your phone and computer, when you also need to draw on the page or sign it, and when you would prefer the document stays on your device.
Troubleshooting: comments not showing or hard to read
- The other person cannot see your notes. Make sure they opened the copy you downloaded after commenting, not the original from the first email. Different PDF viewers also display comments in their own way, so if in doubt, ask them to open it in a full PDF reader rather than a quick preview.
- The note covers important text. Place it in nearby white space and add an arrow with Shapes pointing at the spot.
- You need the comments to print. Some viewers hide notes when printing. If the words must appear on paper, use Add text in a coloured font instead.
- The file asks for a password. You need that password to open it; Unlock can remove a password you already know.
Questions people ask
How do I add a sticky note to a PDF?
Open the PDF in Quick PDF, choose Comment in the toolbar, tap where the note should go, and type. The sticky-note comment stays on that spot of the page and is saved into the file when you download it.
Can I comment on a PDF without Adobe Acrobat?
Yes. Quick PDF runs in your web browser, so you can add comments on a phone, Mac, Windows PC or Chromebook without installing Acrobat. Mac Preview and Microsoft Edge also have basic note tools.
Can I reply to someone else’s comment?
Quick PDF is for marking up a document yourself, not for threaded discussions. The simplest approach is to add your own comment right next to theirs, starting with your initials, and send the file back.
Will comments change the original text?
No. Comments sit on top of the page. The wording of the document stays exactly the same, which is why comments are the right choice when you are reviewing something you should not edit yourself.
How do I delete a comment I just added?
While the PDF is still open, tap Undo to remove your last change, and Redo if you undo too much. It is worth reading through your notes once before you download the final copy.
Is it safe to comment on a confidential PDF online?
Quick PDF opens the file inside your browser on your own device, so it is not uploaded to a server for editing. For sending it on afterwards, see our guide on sending a PDF securely.
Do I have to pay to use Quick PDF?
You can open a PDF and edit, sign or fill it after signing in with Google or email. To download, print or share the finished file you start a subscription with a free trial: 7 days on the yearly plan ($29.78 per year) or 2 days on the monthly plan ($2.99 per month). You are charged when the trial ends unless you cancel, and you can cancel anytime.
Sign in with Google or email and start editing. Saving your file starts a free trial: 7 days on yearly ($29.78/yr) or 2 days on monthly ($2.99/mo). Cancel anytime. 🔒 Your file stays on your device.