PDF Annotator lets you mark up any PDF: highlight important lines, draw with your mouse or finger, add text notes and boxes, place images and signatures — then save a new PDF. Great for reviewing documents, studying and giving feedback.
How to annotate a PDF
- Click "Choose PDF file" and open your PDF.
- Pick a tool: Highlight, Add text, Box or Draw — then drag or click on the page.
- Use Move to adjust, resize or delete annotations; change colour and size in the toolbar.
- Click "Save PDF" and download the annotated file.
Why use ZentaPDF PDF Annotator?
Easy to useSimple steps, clear buttons — done in a few clicks.
Free, no sign-upNo account, no email, no watermark and no daily limits.
FastNo waiting — results are ready in seconds.
Works everywhereUse it on Windows, Mac, Linux, Android or iPhone in any modern browser.
Original qualityPages are copied as they are — text and images stay crisp.
Large filesHandle big files and many pages — limited only by your device’s memory.
Frequently asked questions
Can I change the highlight colour?
Yes. Select a highlight with Move and pick a new colour in the toolbar.
Can I edit existing text too?
Use our Edit PDF tool to change the original text. The annotator is for adding marks on top.
Will others see my annotations?
Yes. Annotations are saved into the PDF, so they show in every PDF reader.
Is it really free? Do you add a watermark?
Yes, it is completely free with no sign-up, no watermark and no daily limits. The site is supported by a few non-intrusive ads.
Related tools
Edit PDFChange existing text, add text, signatures, images, shapes, arrows and highlights.Sign PDFDraw, type or upload your signature and initials, and sign every page at once.PDF ReaderOpen and read PDFs online with zoom, search and print.Add WatermarkStamp text or an image over your PDF pages.
More Edit PDF tools
- Add Page Numbers
- Crop PDF
- Flatten PDF
- Edit Metadata
- PDF Form Filler
- PDF Overlay
- Change Page Size
- Grayscale PDF