Adding text to a PDF sounds simple, but most tools make it harder than it should be. Desktop PDF editors are expensive. Online tools that "edit" PDFs usually upload your file to a server before you see anything. And many free tools only let you add comments, not permanent text.
The Edit PDF tool at FixMyPDF renders your document in a browser canvas and lets you place text boxes, highlights, and shapes directly on the page. When you download, those annotations are written permanently into the PDF.
Free Edit PDF — runs in your browser
Add text, highlights, and shapes. No upload required.
Open Edit PDFWhat the Edit PDF tool does (and doesn't do)
This is an annotation editor, not a text replacement editor. That distinction matters.
What it does: places new content on top of your PDF pages. You can type text at any position, draw highlight overlays, and add rectangle shapes. These are overlay annotations — they sit on top of the existing page content and are saved into the PDF file when you download.
What it does not do: reflow, replace, or delete text that is already in the PDF. If you need to change "2024" to "2025" in an existing paragraph, that requires a true text editor like Adobe Acrobat Pro or LibreOffice Draw. Modifying existing PDF text at the character level requires access to the original text stream, font encoding, and layout engine — well beyond what a browser-based tool can do reliably.
For most annotation tasks — adding a signature line label, marking up a document for review, adding comments, drawing attention to a section — the overlay approach works exactly as needed.
How to annotate a PDF step by step
Open the Edit PDF tool
Upload your PDF
Drag your file onto the drop zone or click to browse. PDF.js renders a visual canvas of each page — nothing is sent to a server.
Select a tool and click to place
Choose Text to add a text box, Highlight to mark a region, or open the Shapes dropdown to pick Rectangle, Square, Oval, or Line. Click Image to embed a photo or image. Click anywhere on the page to place an element. Drag it to reposition. Double-click a text item to edit the text content.
Adjust styling options
For text: set font family, size, and color in the toolbar. Toggle bold or italic. For rectangles: choose border color and fill. The toolbar updates to show the relevant options for the selected item type.
Download the annotated PDF
Click Download. pdf-lib flattens your annotations into the PDF page structure. The output file shows all annotations in any PDF viewer — no special software needed.
Text, highlight, and rectangle — when to use each
| Tool | What it creates | Good for |
|---|---|---|
| Text | A draggable text box at any position | Labels, signature line instructions, filling in blank fields, adding a date, notes in margins |
| Highlight | A semi-transparent color overlay | Drawing attention to a clause, marking passages for review, visual callouts |
| Rectangle | An outlined or filled rectangle shape | Boxes around sections, redaction-style coverage (filled black), diagram callouts |
| Square | A 1:1 aspect-ratio outlined or filled box | Square callout boxes, stamps, icon placeholders |
| Oval | An outlined or filled ellipse shape | Circling important text or figures, oval callouts |
| Line | A straight line with draggable endpoints | Arrows (when combined with text), dividers, diagram connectors |
| Image | An embedded JPG or PNG image | Logos, signatures, stamps, diagrams placed on the page |
All three can be combined on the same page. A common workflow is to draw a highlight over the relevant section, then add a text box in the margin with a note explaining it.
Repositioning and editing items
While the Select tool is active, click any annotation to select it, then drag to move it anywhere on the page. For text items, double-click to enter edit mode and change the content directly. Click elsewhere to deselect.
To delete an item, select it and press the Delete key (or use the remove button in the toolbar if available).
Are annotations saved permanently?
Yes. When you click Download, pdf-lib converts the overlay annotations into native PDF content streams embedded in each page. The annotations become part of the page itself — they are not a separate annotation layer that could be toggled off.
Recipients do not need any special software or viewer to see the annotations. They display correctly in Adobe Reader, Chrome's built-in PDF viewer, Preview on macOS, and any other standard PDF viewer.
One implication: the annotations are also not editable after download. If you need to adjust placement or text, re-open the original PDF (not the annotated version) in the tool and redo the annotation.
Why browser-based matters
PDF annotation tools that run on a server receive your entire document in order to process it. For documents containing contracts, financial data, medical information, or personal details, that is a meaningful privacy exposure.
FixMyPDF renders pages and processes annotations entirely in your browser using PDF.js and pdf-lib. The document stays on your device. No bytes of your content travel over the network at any point in the process.
Frequently asked questions
Can I edit existing text in the PDF?
What annotation types does the tool support?
Are annotations saved permanently into the PDF?
Can I annotate a multi-page PDF?
Can I fill in a PDF form using this tool?
Is my file uploaded to a server?
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