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Sign PDF — Stamp a Signature Image

signature image · pick position · in your browser

Drop a PDF, drop a signature image (PNG with transparency works best), pick where on the page to stamp it, and download the signed file. This is a visual stamp — not a cryptographic signature. For legally binding e-signatures, use a service that produces a PKI signature.

Drop your PDF file here

One PDF at a time · then drop a signature image below

    no files
    Ready.

    When to use this tool

    Quick visual signing — contracts you've agreed to, claim forms, school permission slips. The output is a normal PDF with a stamped image on the chosen page(s). If counterparties demand a verifiable signature, use a dedicated e-signature service that produces a PKI-backed signature dictionary.

    How to sign a PDF

    1. Make a clean signature image. Photograph or scan your signature, remove the background, save as transparent PNG. A 600px-wide PNG is plenty.
    2. Drop the PDF. Then drop the signature image into the file picker.
    3. Pick page(s) and position. "last" stamps only the last page; "all" stamps every page.
    4. Click "Sign & download". Output is name-signed.pdf.

    FAQ

    Is this a legal e-signature?

    No — it's a visual stamp. Whether a visual stamp is binding depends on jurisdiction and counterparty agreement. Use a dedicated e-signature service if you need cryptographic proof of who signed when.

    Why does my signature look boxy?

    JPEG signatures have a white background that won't blend with the page. Convert to PNG and remove the background first.

    Are my files uploaded?

    Never — this runs entirely in your browser via pdf-lib. See the privacy policy.

    How do I make a signature image with a transparent background?

    Sign a white sheet, photograph or scan it, then run it through a background remover — pngtoolskit.org has one. A PNG with real transparency sits on the page; a JPG always brings its white rectangle with it.

    Can I sign on a phone or tablet?

    Yes. The page works on mobile, and the easiest route is to sign on paper, photograph it, remove the background and stamp that PNG.

    Where should the signature go on a contract?

    Wherever the signature block is. Pick the position and page, set the width as a percentage of the page so it scales sensibly, then check the output before sending.

    Is a stamped image a legally binding signature?

    It is an image of a signature, not a cryptographic digital signature, and it carries no certificate or tamper evidence. For many everyday documents that is accepted; where a qualified electronic signature is required by law or by the counterparty, use a service that issues one.