PDFStack Tool
Sign PDF Online — Free Electronic Signature Tool
Draw your handwritten signature and stamp it onto any PDF page directly in your browser. PDFStack's sign tool uses an HTML5 canvas for silky-smooth drawing, then embeds your signature as a transparent PNG into the PDF at your chosen position.
Open Sign PDF →
No file uploads
No account required
Free to use
Private & secure
Why sign PDFs with PDFStack?
DocuSign and Adobe Sign are expensive for personal or low-volume use. PDFStack's free PDF signing tool lets you draw a handwritten signature and place it anywhere on a PDF — legally valid as an electronic signature in most jurisdictions — with zero cost and zero file upload.
How to sign a PDF
- 1Open Sign PDF in PDFStack.
- 2Upload your PDF.
- 3Draw your signature on the canvas using your mouse, stylus, or finger.
- 4Set the page number, size, and X/Y position.
- 5Click Apply Signature and download the signed PDF.
All processing happens locally in your browser — no files are uploaded to any server.
Common Uses
Signing contracts, lease agreements, consent forms, NDAs, or any document that needs your signature before returning it digitally.
Frequently Asked Questions
Is a drawn signature legally valid?
Yes. In most countries (including under ESIGN in the USA, eIDAS in the EU, and ECTA in South Africa) a handwritten electronic signature is legally binding when applied with intent to sign.
Can I sign on mobile?
Yes — use your finger on the canvas to draw your signature on a touchscreen device.
Can I reuse my signature?
PDFStack clears the canvas each session for privacy. Draw fresh each time or prepare a saved PNG to upload via the stamp feature.
Is my document private?
Completely. Your PDF and signature never leave your device.