How to Edit Text and Add Annotations to a PDF
September 23, 20265 min readWhy most PDF editing is really markup on top of the page, what you can add, and a simple workflow for annotating a document quickly.
Most PDFs aren’t meant to be rewritten from scratch — you just need to add a note, fill in a missing detail, mark up a section, or drop in a logo. That’s markup and annotation, and it’s a very different job from full document editing.
Editing vs. annotating a PDF
A PDF doesn’t store text the way a word processor document does — there’s no paragraph you can click into and retype. What most “PDF editors” actually do (and what the Edit PDF tool does) is add new content on top of the existing page: text boxes, shapes, freehand marks, and images, positioned exactly where you place them and baked into the page when you export.
What you can add
- Text boxes — pick a color and font size, click to place, type your text.
- Rectangles and lines — useful for highlighting a section or drawing attention to something.
- Freehand strokes — sketch a note or circle something by hand.
- Images — drop in a logo, stamp, or diagram at a size and position you control.
A simple workflow
- Upload your PDF and navigate to the page you want to mark up.
- Choose a tool — text, rectangle, line, freehand, or image.
- Click (or click-and-drag) on the page to place your edit.
- Repeat across pages, using undo or clear-page if you make a mistake.
- Apply your edits and download the new PDF.
Keeping it simple, on purpose
This toolset is deliberately small — text, shapes, freehand, and images — rather than trying to match a full desktop publishing app. That keeps it fast, predictable, and honest about what it does: it marks up your PDF, it doesn’t rewrite the document’s original text. If you need to place a signature specifically, the dedicated Sign PDF tool has drag-and-resize placement built for that. And if you need to permanently remove sensitive content rather than mark over it, see Redact PDF — drawing a colored box with the editor is not a substitute for real redaction, since the original content underneath would still be there.
A note on privacy
Every edit is rendered and baked into the PDF locally, using pdf-lib and pdfjs in your browser. Your file is never uploaded anywhere.