Add Signature to PDF lets you place a signature — drawn on the spot or uploaded as an image — onto any page of a document, entirely inside your browser. It's built for the everyday case of needing to sign a form or contract without printing it, signing it, and scanning it back in. It's worth being upfront about what this is not: it produces a cosmetic image signature, not a cryptographic or PAdES digital signature, so it doesn't carry the tamper-evidence or identity-verification guarantees that format provides. For most everyday paperwork, a visual signature is exactly what's needed; for contracts requiring verifiable digital signing, you'll want a dedicated e-signature service instead.

Drawing a signature uses a small canvas that tracks pointer input directly — mouse, trackpad, or touchscreen all work the same way — building up a transparent-background image of your strokes as you draw. If you'd rather reuse an existing signature, the "Upload" tab accepts a PNG or JPEG image instead.

Once you have a signature ready, drag it into position over the page preview and resize it using the corner handle until it fits naturally. Behind the scenes, the position you see on screen is converted from the preview's pixel coordinates into the PDF's own coordinate system — which, unlike a typical image editor, measures from the bottom-left corner of the page rather than the top-left — so the signature lands exactly where you placed it. The image is then embedded directly into that page's content, the same technique used for adding any image to a PDF, which is why it becomes a permanent part of the page rather than a movable annotation.

Every step — rendering the page preview, capturing your drawn signature, and producing the final signed PDF — happens in your browser's memory. Nothing is uploaded, and the signed file only leaves your device when you choose to download it.