Drop a PDF file or click to browse. PDF.js renders it instantly in your browser — nothing is uploaded.
2
Annotate
Use the toolbar to add text, draw freehand, or highlight areas. Switch between tools and adjust color and stroke width.
3
Export PDF
Click Export to flatten all annotations into the PDF and download. The original pages are preserved with your markups embedded.
FAQ
What can I do with this PDF Editor?
Add text annotations, freehand drawings (great for signatures), and highlight regions on any PDF page. All annotations are flattened into the PDF when you export, so recipients see exactly what you marked up.
Is my PDF uploaded to a server?
No. Everything runs in your browser using PDF.js for rendering and pdf-lib for export. Your file never leaves your device.
Can I edit the existing text in a PDF?
This tool focuses on annotations — adding text, drawing, and highlighting on top of the PDF. It does not modify the original text content. For text extraction, try our PDF to Word converter.
How does export work?
When you click Export, each annotation layer is rendered as an image and embedded onto the corresponding PDF page using pdf-lib. The result is a standard PDF with your annotations baked in.
Is there a page limit?
No hard limit. Performance depends on your device — most PDFs up to 200 pages work fine. Very large files may take a moment to render.
Can I undo my annotations?
Use the Eraser tool to click on any annotation (text, drawing stroke, or highlight) to remove it. You can also clear all annotations on the current page.
Can I use this to sign PDFs?
Yes. Use the freehand Draw tool to create a handwritten signature on any page. Adjust stroke color and width to match your preference. The signature is flattened into the PDF on export, so recipients see it as part of the document.
Does it work on mobile?
Yes. The editor works on mobile browsers — upload a PDF and use touch to draw or add text. Drawing is especially natural on tablets with a stylus. For best results with complex annotations, use a desktop browser.
How does this compare to Adobe Acrobat or Smallpdf?
Adobe Acrobat is the gold standard but requires a subscription. Smallpdf uploads your files to their servers. Our editor runs 100% in your browser — your PDF never leaves your device. The tradeoff is we focus on annotations (text, draw, highlight) rather than full text editing.
What if I need to edit the actual text in a PDF?
This tool adds annotations on top of existing content. To extract and edit the underlying text, convert your PDF with <a href="/ai/pdf/pdf-to-word">PDF to Word</a>, make changes in a word processor, then convert back with <a href="/ai/pdf/word-to-pdf">Word to PDF</a>.
Can I merge annotated PDFs with other documents?
Yes. After exporting your annotated PDF, use our <a href="/ai/pdf/merge">PDF Merge</a> tool to combine it with other PDFs. Annotations are baked into the exported file, so they appear correctly in the merged document.
Is there a file size limit?
No strict limit, but performance depends on your device. PDFs up to 50MB and 200 pages typically work well. Very large architectural or image-heavy PDFs may render slowly. You can use our <a href="/ai/pdf/compress">PDF Compressor</a> to reduce file size first.
Can I highlight text for review?
Yes. Select the Highlight tool, choose a color, and drag over any area to highlight it. This is useful for marking up contracts, research papers, or any document that needs review annotations.
Coda One's PDF Editor lets you annotate any PDF directly in your browser. Add text boxes, draw freehand signatures or marks, and highlight important sections. All processing uses PDF.js for rendering and pdf-lib for export — your files never leave your device. No signup, no watermarks, completely free.