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Editing & Signing

How to Add a Seal or Stamp Image to a PDF

Add a seal or stamp image to a PDF for an official look. Upload a transparent PNG, size it, place it per page. Free, in-browser, private.

HM

Hamza M.

PDF Workflow Editor

September 24, 20263 min readReviewed September 24, 2026

A round official seal, a company stamp, an approval mark — adding an image like these to a finished PDF is a common finishing step before a document goes out. The Sign PDF tool treats an image exactly like a signature: you upload the stamp file, place it on the page, size it, and download the result. No digital signature certificate is involved — it is a visual mark on the page.

What a stamp image actually is

An image stamp is a picture drawn over the page. Your uploaded PNG or JPG is placed at a position you choose, scaled to a size that suits the document, on the page you select. It behaves like a rubber stamp laid on the paper — it covers what is below it, so place it over a clear area of the page.

Add a seal or stamp to a PDF, step by step

  1. 1Open the Sign PDF tool and drop in your file.
  2. 2Choose the image option and upload your seal or stamp as a PNG.
  3. 3Adjust the size with the scale control so the stamp fits its spot without dominating the page.
  4. 4Place the stamp where you want it on the current page, then repeat on any other pages that need it before downloading.

Because each placement is on a specific page, the same stamp can sit on page one and on an approval page later in the document — you just drop it in both places with the same image file.

Preparing a clean stamp image

  • Use a PNG with transparency so only the seal itself covers the page.
  • Export at a sensible resolution — a massive scan becomes pixel-heavy when shrunk; aim for the size it will print at.
  • Keep the file lightweight; a small image places instantly and keeps the PDF lean.

One page, every page, or a watermark?

Stamps and seals are page-level marks, so place them where they belong — usually the cover, an approval page, or a certification line. For continuous background branding such as a corner logo or DRAFT label across every page, a watermark is the right tool instead, because it repeats for you. A hand-placed seal is about a specific official spot, which is exactly where the stamp belongs.

Do it now

Sign PDF

Add digital signatures to PDFs. It runs in this browser tab — your file is not uploaded anywhere.

Open Sign PDF

Frequently asked questions

Does an image stamp make the PDF legally official?+

A placed image is a visual mark on the page — it does not carry the cryptographic proof or verification process of a notary. It works for brand presence and internal approval; an officially notarized stamp requires the notary's own physical or digital notarization process.

Will the stamp look boxy or pixelated?+

Only if the source has a background or too little resolution. Use a transparent PNG, size it with the scale control, and export at the size it will print at — then it reads like a real seal.

Can I put the same stamp on several pages?+

Yes. Upload the image once, then place it on each page that needs the mark, sizing each placement to fit. The tool works page by page.

What is the difference from a watermark?+

A watermark is applied automatically to every page for continuous branding. A stamp is placed by hand at a specific spot on specific pages — an official corner, an approval block, a cover page.

Can I remove a stamp I placed by mistake?+

Re-run the flow: reopen the file the same way and place the corrected stamp, or re-export from your last good download. Placement is part of the page you save.

Keep reading

HM

Hamza M. · PDF Workflow Editor

Hamza has spent a decade working with print and digital documents — from prepress production to everyday PDF cleanup — and now writes practical, tested guides for Slate PDF.

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