Guide

Add a signature to a PDF

Many forms only need a visible signature on the page: a permission slip, a simple acknowledgment, an internal approval. RealScaner’s signature maker draws that mark in the browser, or cleans up a photo of a signature you wrote on paper, and lets you download an image you can place on the PDF. Sign PDF places that signature, plus a typed name or date if you need them, directly on the PDF pages. The pages are not turned into images, so the text stays selectable. Both make a simple electronic signature: a visible mark that you place yourself, right in the browser.

Choose the mark

A drawn signature looks closest to pen on paper. Use a mouse only if you must; a trackpad or a finger on a phone produces a smoother line. Sign larger than you need, then scale it down on the page so the strokes stay dark. When the instructions say “type your name,” type it into the form’s own name field instead of drawing it; a typed name is clearer for people who cannot read your handwriting. Match the name to the printed name on the form.

Keep the background transparent or white. A photo of a signature on lined paper brings the lines with it. Crop tight around the ink, then place the image on the signature line rather than over the paragraph above it.

Place it so the form still reads

• Sit the image on the signature line, not across neighboring fields.
• Leave the date line empty if the form asks you to write the date by hand or type it separately.
• Do not cover terms, totals, or someone else’s signature.
• Export the finished PDF and open it once before you send it. Some viewers drop images that sit outside the page box.

What this is not

A picture of a signature can be copied. If the PDF already carries a certificate-based digital signature, adding yours invalidates it, and Sign PDF warns you before it saves. If a bank, court, or government site asks for a qualified or certified electronic signature, follow that site’s own signing flow. Do not send a signed file that still contains blank pages or an older unsigned copy behind the signed one. Reorder or delete those pages in Organize PDF first. If the form is public and you want a faint ownership mark on every page, that is a different job: use Watermark PDF, not the signature image.

Updated October 21, 2026. First published September 25, 2026.

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• When a phone scan is good enough

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  When shrinking images inside a PDF helps, and when a smaller file starts to look worse.

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