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HomePDFSign PDF

Sign PDF

Draw a signature, drag it onto the page, save a signed PDF. Free, private, runs in your browser.

100% private — your files never leave your browser. All processing happens locally on your device.

Choose a file

or drop it here · paste from clipboard

PDF·Up to 100MB

Draw your signature, drag it onto any page, save the signed PDF. Files never leave your device.

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Why Sign a PDF in the Browser

Most PDF signing tools upload your file to a server, wait for you to draw the signature on their page, then give you back a copy. That model has been standard for a decade, but it has one obvious flaw: every document you sign — including leases, NDAs, medical forms, financial agreements — sits on a third party's disk for the duration of the session, and often longer. The client-side approach we use keeps the file on your device at every step. The pages are rendered in your browser. The signature is drawn on a canvas in your browser. The stamp is written back into the PDF by pdf-lib, also in your browser. Nothing is transmitted.

How the Signature Becomes Part of the PDF

When you draw on the signature pad, it records your strokes as vector paths. On save, the tool rasterises those strokes to a transparent PNG, trims the empty margins, then embeds the PNG as an image on the page you picked, at the position and width you dragged. The underlying pdf-lib library writes a new image XObject into the PDF and places it at the requested coordinates. The rest of the PDF — text, other images, metadata — is preserved exactly. You can re-sign or add a second signature by re-running the flow on the already-signed PDF.

Typed vs. Drawn Signatures

A drawn signature (the kind this tool produces) reads as more personal and is harder to fake than a typed font. It's what you'd get from a tablet-signing flow at a bank. Typed cursive fonts are easier and good enough for many internal workflows; if you prefer that, generate your signature elsewhere as a PNG and use an image-on-PDF tool to stamp it. For pen-drawn results, use your phone — touch input beats mouse drawing.

Is It Legally Binding?

In most jurisdictions, a visible signature stamp has the same legal weight as a pen-and-paper signature for everyday agreements — rental forms, employment docs, internal approvals. What a pure visible stamp does NOT provide is a cryptographic audit trail proving which keys signed it and when. For that level (eIDAS advanced e-signature, HIPAA, SEC filings), use a certified e-signature service that issues digital certificates. For everything else, a visible signature is fine and often expected.

FAQ

Is my PDF uploaded anywhere?

No. Everything — rendering the pages, drawing the signature, stamping it into the PDF — runs in your browser. Your file never leaves your device.

Is this a legally binding e-signature?

A visible signature stamp is sufficient for many everyday agreements (forms, rental docs, internal approvals). For contracts requiring digital certificates (eIDAS, DocuSign-style audit trails), use a certified e-signature service.

Can I sign a specific page?

Yes. Use the page picker to navigate to the page you want, then drag your signature anywhere on that page before saving.

Can I sign on my phone?

Yes — the signature pad supports touch input. Just use your finger to draw on the canvas.