1. Upload PDF
Drop PDF here or click to upload
2. Draw Your Signature
Size:
3. Click on PDF to place signature
Processing...
Files processed locally — never uploaded
Also try: AI Humanizer · Summarizer · Rewriter 3 free uses/day
How It Works
1
Upload your PDF
Drop a PDF or click to browse.
2
Draw or upload signature
Draw with mouse/finger, or upload a signature image.
3
Place and download
Click on the PDF to position your signature, then download.
FAQ
How does PDF signing work?
Draw your signature on the canvas or upload a signature image. The tool uses pdf-lib.js to embed the signature at your chosen position on the PDF. All processing happens in your browser — your document never leaves your device.
Is this a legally binding digital signature?
This tool adds a visual signature image to a PDF. It is not a cryptographic digital signature (PKI). For legally binding e-signatures, services like DocuSign or Adobe Sign provide certificate-based authentication. Our tool is suitable for informal documents, internal approvals, and quick sign-offs.
Can I draw my signature with a mouse?
Yes. The canvas supports mouse and touch input. Use your mouse on desktop or draw with your finger on mobile. You can also upload a pre-existing signature image (PNG with transparent background works best).
Can I position the signature anywhere on the page?
Yes. Click on the PDF preview to place your signature. Drag to reposition. The signature is placed at the exact coordinates you choose.
Is my PDF uploaded to a server?
No. pdf-lib.js runs entirely in your browser. Unlike <a href="/ai/pdf/protect">password protection</a>, signing adds a visual element. Your document never leaves your device.
Can I sign multiple pages?
Currently you can sign one page at a time. After downloading, you can re-upload to add signatures to additional pages.
What signature image formats are supported?
PNG (recommended, supports transparency), JPG, and WebP. For best results, use a PNG with a transparent background.
Can I change the signature size?
Yes. Use the size slider to adjust the signature width. Height scales proportionally.
Can I undo and re-sign?
Yes. Click "Clear signature" to redraw. The PDF is not modified until you click "Apply Signature".
Does it work on mobile?
Yes. Draw your signature with your finger on the touch canvas. The PDF preview and placement work on mobile screens.
What is the file size limit?
Depends on your device. Most devices handle PDFs up to 50MB comfortably.
Can I remove a signature from a PDF?
Not with this tool. Once a signature is embedded and saved, it becomes part of the PDF content. Always preview before downloading.
Does it preserve the original PDF quality?
Yes. pdf-lib.js modifies the PDF without re-rendering. Try also <a href="/ai/pdf/editor">PDF Editor</a>. All existing content, formatting, and quality remain intact.
Is it really free?
Yes. Completely free, no limits, no signup required.
Can I pay with cryptocurrency?
PDF tools are free. For AI writing tools, we accept USDT, USDC, BTC, ETH. Plans start at $9.99/month.
Do more with your documents
Summarize, rewrite, or translate the text in your PDFs with AI.
Coda One's PDF Signer lets you add your handwritten signature to any PDF document. Draw directly on the canvas or upload a signature image. Position it precisely on the page. Uses pdf-lib.js entirely in your browser — no uploads, no servers.