Sign PDF
Add your signature to a PDF in seconds. Draw it with your mouse or finger, or type your name in a signature style, then click the page to drop it exactly where you want. Everything runs in your browser — your file never leaves your device.
1. Create your signature
Draw with your mouse or finger inside the box.
🔒 Your PDF and signature are processed entirely in your browser. Nothing is uploaded to any server.
Understanding the Sign PDF
Sign PDF lets you add a handwritten or typed signature to any PDF without installing software or creating an account. Draw your signature with a mouse or finger, or type your name in a cursive or serif style, then click directly on a live preview of the page to drop it exactly where it belongs. A size slider and page selector handle multi-page documents and different signature sizes. It is built for freelancers, contractors, and anyone signing forms, NDAs, or approvals. Because it runs 100% in your browser, your PDF and signature never touch a server — nothing is uploaded, making it safe for confidential and personal documents.
How it works
The tool loads pdf.js in the browser to render the chosen page to a canvas at a fit-to-width scale. Your drawn strokes (captured via pointer events) or typed text are painted onto an off-screen canvas, then auto-cropped to a tight, transparent PNG. When you click the preview, the tool records an anchor point in canvas pixels. On apply, pdf-lib loads the original PDF, embeds the PNG with embedPng, and draws it on the target page. Click coordinates are converted from the canvas (top-left origin) to PDF points (bottom-left origin) using the render scale and page height, so the signature lands precisely where you placed it. The result is saved with a temporary download link.
Worked example
You upload a one-page rental agreement. On the Draw tab you sign with your trackpad and click Use this signature; the tool crops it to a 300x100 px transparent PNG (ratio 3.0). The page renders at scale 0.85. You set the size slider to 180 px and click near the bottom signature line, anchoring at (210, 540). On apply: drawWidth = 180 / 0.85 ≈ 212 pt, drawHeight ≈ 71 pt, pdfX ≈ 247 pt, and pdfY = 792 - (540 / 0.85) - 71 ≈ 86 pt. The signature appears exactly on the line, and agreement-signed.pdf downloads.
Tips & common mistakes
- Draw slowly for smoother strokes; use Clear to redo if a line looks shaky before clicking Use this signature.
- The signature is auto-cropped to remove empty margins, so it sits tightly at the point you click — click where you want its center.
- Use the Size slider before placing on small pages; an oversized signature is clamped to stay inside the page bounds.
- For multi-page PDFs, pick the page from the dropdown first — the preview re-renders and you place the signature on that specific page.
- This adds a visual signature image only. For legally binding agreements needing audit trails and identity verification, use a certified e-sign service like DocuSign or Adobe Sign.
- Password-protected or corrupted PDFs cannot be opened in-browser; remove the password first if you see an error.
Related tools
How to Sign a PDF
- 1Upload or drag in your PDF file.
- 2Draw or type your signature, then pick the page and size.
- 3Click the preview to place it and hit Sign & download — your signed PDF saves automatically.
Frequently Asked Questions
Can I draw my signature or type it?
Both. Use the Draw tab to sign with your mouse or finger on a touch screen, or switch to the Type tab to render your name in a cursive or serif style. Either way you get a clean, transparent signature you can place on the page.
Is this a legally binding e-signature?
It adds a visual signature image to your PDF, which is fine for everyday forms and approvals. For legally binding workflows with audit trails and identity verification, use a certified e-sign service such as DocuSign or Adobe Sign.
Is my PDF uploaded anywhere?
No. The PDF is rendered and signed entirely in your browser using JavaScript. Your document and signature never leave your device and are not sent to any server.