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Stamp an Image on a PDF

logo · signature · image watermark · position, scale, opacity

Place a PNG or JPG on some or all pages of a PDF — a logo in the corner, a scanned signature at the bottom, a semi-transparent APPROVED graphic across the middle. Set the corner, the size as a percentage of page width, the opacity and the rotation.

Drop PDF files here or click to select

One or many · the same stamp on each

    no image chosen
    no files
    Ready.

    No PDF handy? Try sample-10-pages.pdf. More free sample files.

    Three jobs it does well

    Getting the image right

    PNG is the format to use when the stamp has transparency — a logo on a white rectangle looks like a sticker, while a transparent PNG sits on the page properly. JPG is fine for a photographic stamp with no transparency and produces a smaller file.

    Aspect ratio is preserved: you set the width as a percentage of the page and the height follows. Very large images make very large PDFs, since the image is embedded once per document — resize a 4000-pixel-wide logo down before stamping if the output size matters.

    Placement

    Position picks the anchor corner (or the centre), and margin is the distance from the page edge in PDF points — 72 points to the inch, so 24 points is a third of an inch. Rotation turns the image around its own placement; a 45-degree rotation with centre placement is the classic diagonal watermark look. The stamp is drawn on top of the existing content, so it will cover whatever is underneath — reduce the opacity if that matters.

    FAQ

    Does transparency work?

    Yes, for PNG. The alpha channel is preserved, so a transparent background stays transparent. JPG has no alpha, so it always paints a rectangle.

    Can I put it behind the text instead of on top?

    Not with this tool — the stamp is drawn over the page content. Lowering the opacity to 0.1–0.2 gives the same visual effect as a background watermark for most documents.

    How do I stamp just the last page?

    Type the page number in the Pages field. The field takes single pages and ranges, like 1,3-5. There is no "last" keyword, so check the page count first.

    Is the stamp editable or removable afterwards?

    It is drawn into the page content, so it is not an annotation and cannot be toggled off in a viewer. Keep your original if you might need the unstamped version.

    Are my files uploaded?

    No. Both the PDF and the image stay in your browser.

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