Annotate PDF

Highlight, underline, strike through and comment. Marks are written as real PDF annotations, so they stay editable in Acrobat and every other reader.

Why annotate a PDF?

A comment typed into a chat window sits next to the document, not on it. An annotation is attached to the exact words it refers to, so the reviewer sees the remark where they need it.

Highlight, underline, strike through and comment

Marks are written as real PDF annotations, editable in Acrobat and every other reader

Your comments travel with the file and can be removed later

Colour, thickness and opacity under your control

One shared author name shown against every comment

No layout shift — annotations sit over the page, never reflow it

How to Annotate PDF

Choose your PDF

Upload the document you want to review or mark up.

Mark it up

Pick a tool, then drag across the text to highlight, underline or strike through it. Add a comment for anything that needs a written note.

Save and share

Save the annotations and download or share the marked-up file.

100% Secure

AES-256 encryption

Super Fast

Results in seconds

Auto-Delete

Files removed in 2 hours

Frequently Asked Questions

Are the annotations real PDF annotations?

Yes. They are written as native PDF annotation objects, so Acrobat and every other reader treat them as comments rather than as drawn shapes.

Can I remove them later?

Yes, each annotation can be removed without touching the page content underneath it.

Does annotating change the layout?

No. Annotations are an overlay object in the file, so nothing reflows and the original text stays exactly where it was.

Ready to annotate pdf?

Upload your file above and get started instantly. No account needed — 4 free tasks per month.

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