Annotate a PDF
Highlight the important parts, scribble in the margins, stamp text where it's needed. Annotations are baked into the page itself, so they look identical in every viewer and can't be accidentally deleted.
How it works
- Drop your PDF and pick a tool: Highlight (drag over text), Pen (draw freehand) or Text (click, type, Enter).
- Mark up any page. Use Prev/Next to move through the document. Undo removes the last mark; “Clear this page” starts a page over.
- Save. Everything is drawn into the page content and the annotated PDF downloads instantly.
Frequently asked questions
Will my highlights show up in other PDF viewers?
Yes — identically, everywhere. They're baked into the page content itself (with a multiply blend, so highlighted text stays perfectly readable), not added as fragile pop-up annotations that some viewers hide or render differently.
Can annotations be removed later?
No — they become part of the page, like ink on paper. That's the point for markups you're sending onward. Keep your original file if you want an unmarked copy.
Can I add comments that pop up on hover?
Not with this tool — it deliberately creates permanent, flattened markup rather than interactive comment bubbles, so the result is tamper-proof and renders the same everywhere.
Is my document uploaded?
No. Annotation happens entirely in your browser — the file never leaves your device.