How to Annotate a PDF Online for Free: Highlight, Draw & Comment
Need to highlight text, add comments, or draw on a PDF for review? This guide shows you how to annotate a PDF online for free—use highlighters, pens, sticky notes, and text boxes, then download the marked-up file. All processing runs in your browser: your document never leaves your device. We cover annotate pdf, markup pdf, highlight pdf text, and when to combine annotations with signing or flattening. No sign-up, no watermarks.
At a glance
Files stay on your device
Highlight, draw, notes
Processed in your browser
No sign-up, no watermarks
Why Use Our Free Annotate PDF?
Mark Up and Review PDFs Without Printing
Collaborating on a draft or reviewing a contract? Our Annotate PDF tool lets you highlight key sections, draw arrows and shapes, add sticky notes, and type comments directly on the page—all in your browser. Better than printing and using a red pen: keep everything digital and easy to share.
Processing runs on your device. Your PDF never leaves your computer, and there are no watermarks or sign-up. Annotate pdf, highlight pdf text, and markup pdf for free in seconds.
Who uses it? Editors, students, legal reviewers, and anyone who needs to leave clear feedback on a PDF without changing the original text.
Premium Features, Zero Cost
We offer the same powerful engines as paid software, but completely free and directly in your browser.
Highlighter
Mark important text in yellow, green, or blue. Perfect for study notes or contract review.
Freehand Drawing
Circle errors, draw arrows, or underline. Great for pointing out specific details.
Sticky Notes & Text
Add comment boxes and type instructions or feedback directly on the page.
100% Private
Your PDF is processed in your browser and never uploaded to our servers.
Works on Tablets
Touch drawing works well on iPads and Android tablets for natural markup.
How It Works Under the Hood
Why Annotate in the Browser
Many review tools upload your PDF to the cloud. We run the annotation layer in your browser so your drafts and contracts never leave your device. Annotations are stored as standard PDF markup (highlights, ink, and comment objects), so the result is compatible with any PDF reader.
In practice: Annotate pdf and markup pdf stay private—ideal for legal, academic, or confidential review. You get a free tool with no sign-up and no watermarks. When you need to lock the markup so it cannot be edited, use our Flatten PDF tool after annotating.
How to Use Annotate PDF in 3 Simple Steps
1. Upload Your PDF
Open the Annotate PDF tool and add your file by dragging it in or clicking to browse. The PDF is read on your device only—we do not upload it. That keeps drafts and contracts private.
If your PDF is password-protected, you must unlock it first. Use our Unlock PDF tool, then open the unlocked file here to annotate.
2. Add Highlights, Drawings & Comments
Select the Highlighter to mark important text in yellow, green, or blue. Use the Pen or drawing tools to circle errors, underline, or draw arrows. Add sticky notes or text boxes to type longer comments. Your annotations are placed on top of the page and stay visible when you download.
Need to edit text in the PDF or fill forms? Use our PDF Editor. To add a signature after reviewing, use Sign PDF. To lock annotations into the page so they cannot be moved, use Flatten PDF when you are done.
3. Download Your Annotated PDF
When you are finished, click to download. The annotated PDF is generated on your device; we do not store it. Recipients can open it in any PDF reader and see your highlights and comments. Annotations become part of the PDF and can be edited or removed in other editors unless you flatten the file first.
To make annotations permanent and non-editable, run the result through our Flatten PDF tool. To add a password before sharing, use Protect PDF.
Who Is This Tool For?
Editors & Reviewers
Leave clear feedback on manuscripts, contracts, or reports without changing the original text.
Students
Highlight key passages in lecture slides or papers and add study notes.
Legal
Mark up contracts, depositions, or evidence with highlights and comments for colleagues or counsel.
Design Feedback
Circle areas to change, draw arrows, and add notes on PDF mockups or proofs.
Troubleshooting Common Issues
I cannot annotate; the file seems locked.
If the PDF is password-protected, you must unlock it first. Use our Unlock PDF tool, then open the unlocked file here.
I need to edit the actual text, not just annotate.
This tool adds markup on top of the page. To change the underlying text or fill form fields, use our PDF Editor. For scanned PDFs, run OCR PDF first to make text editable.
People Also Ask
How do I highlight text in a PDF for free?
Use MyPocketPDF Annotate PDF. Upload your file, choose the highlighter, select text, and download. Processing is in your browser—no sign-up.
Learn more →Can others edit my annotations?
After you download, annotations are part of the PDF and can be edited or deleted in other PDF editors. To lock them in, use our Flatten PDF tool.
Learn more →Does it work on tablet?
Yes. Touch drawing works great on iPads and Android tablets for natural highlighting and drawing.
Learn more →How do I add a signature after annotating?
Download the annotated PDF, then open it in our Sign PDF tool to add your signature. You can also use the PDF Editor for both annotations and signature.
Learn more →Common Mistakes to Avoid
✕ Expecting to edit the original text
Solution: Annotate PDF adds markup on top of the page. To change the actual text, use our PDF Editor or PDF to Word for editable content.
Tip: Use annotations for review feedback; use the editor when you need to fix wording or fill forms.
✕ Trying to annotate a protected PDF
Solution: Password-protected PDFs must be unlocked first. Use our Unlock PDF tool, then annotate the unlocked file.
Tip: Re-protect with Protect PDF after downloading if needed.