Annotate PDFs right on your device

Annotate and mark up PDFs online

Highlight, comment, draw and add notes to PDF documents

Select or drop a PDF file

Select PDF file

PDF files only

Max 100 MB

🔒 Processed on your device · Never uploaded to a server · Free

  • Easy to use
  • Secure
  • Preserve quality

Processed on your device

Files are not uploaded to CookPDF servers

The main operation runs in the browser on your device.

Session can be restored

The browser can save a cache and local draft to continue your latest work.

Check before using

Review the resulting file, especially for documents that need to be signed, printed, or sent officially.

How to annotate a pdf

Follow three steps and check the result before downloading.

  1. Open the PDF

    Choose the document you need to read and respond to.

  2. Add annotations

    Highlight, draw or place comments on the relevant content.

  3. Review and share

    Check the marks you added, then download the result file.

Highlights

Useful capabilities for the right task on PDF documents.

Multiple markup styles

Combine highlights, drawings and comments to suit your review.

Contextual feedback

Place notes right next to the content they refer to.

Great for review rounds

Create an annotated copy to send back to the author.

Processed locally

Files are processed in the browser on your device.

Use cases

Common situations well suited to this tool.

  • Review documents

    Flag errors and add suggested edits.

  • Study and research

    Highlight key ideas and take notes while reading a document.

  • Internal discussion

    Place comments right on the relevant table, figure or paragraph.

Ready to annotate your pdf?

Choose your PDF files to get started and check the result right in your browser.

Annotate PDF

Annotate and mark up PDFs online

Add comments, highlights, drawings and review marks to a PDF for discussion, review or study.

When is this tool a good fit?

  • Reviewing documents: Flag errors and add suggested edits.
  • Study and research: Highlight key ideas and take notes while reading a document.
  • Internal discussion: Place comments right on the relevant table, figure or paragraph.

Recommended workflow

Open the file, set up the task on the preview, check each affected page, and only then download. Keep the original so you can compare or start over when needed.

Limitations to know

Recipients may use PDF readers that display annotations differently. If you need the appearance preserved, check the file in the application the recipient will use.

Data and session

The main operations run on your device and files are not uploaded to CookPDF servers. Your browser may store a local cache or draft to restore the session; you can clear the session in the interface or clear website data in your browser settings.

Frequently asked questions

Answers about capabilities, limits, and how files are handled.

Can I highlight and draw on a PDF?
Yes. Use the markup tools shown in the editor.
Do annotations change the original content?
Annotations are usually added as an annotation layer or supplementary content and do not rewrite the original text.
Can others delete the annotations?
They can if the annotations remain as annotations and their PDF reader supports editing.
How do I create a copy where annotations can no longer be edited?
You can consider flattening the PDF, but keep the original because after flattening the annotations may no longer be editable individually.

Ready to annotate your pdf?

Choose your PDF files to get started and check the result right in your browser.

Annotate PDF