Stamping a PDF — applying a visual mark like 'Approved', 'Revised', 'Draft', or a custom firm seal — is one of the oldest digital workflows in architecture and construction. The stamp on a shop drawing tells the contractor it's been reviewed. The stamp on a permit set tells the building department it's been signed off. Done well, the stamp is permanent, scaled correctly, and renders identically across every PDF tool the recipient might use. Done poorly, the stamp is a low-resolution image that becomes a tile of pixels when the contractor zooms in. This page covers how to stamp PDFs cleanly, what makes a good stamp, and how Ncored handles the workflow.

What goes wrong with PDF stamps in general tools

Two common problems with stamps in free or general-purpose PDF tools. First, low-resolution stamp images that pixelate when the recipient zooms in for review. Most free online PDF stampers and some built-in stamp libraries use raster images at fixed pixel dimensions — fine at the original zoom level, terrible at 400% zoom on a contractor's screen. Second, stamps that don't travel correctly. Some PDF tools apply stamps as a tool-specific annotation type that the recipient's viewer may not render, leaving the stamped drawing without the stamp on the other side. The architect stamps, the contractor opens the file, the stamp is invisible. For drawings where the stamp is the legal or procedural signal, this is a real failure. The fix in both cases is to use a tool that renders stamps as standard vector or high-resolution image annotations.

How Ncored handles PDF stamps

Ncored's stamp tool applies stamps as standard PDF annotations using either embedded SVG (vector) or high-resolution PNG (raster). Vector stamps scale cleanly at any zoom level — a contractor zooming to 400% sees the same crisp edges as at 100%. The built-in stamp library covers common cases (Approved, Revised, Draft, For Review, As Built, Confidential) and a custom stamp can be created from any image or text in seconds. Stamps are positioned with snap-to-grid for consistent placement across a multi-page set. Saved stamps render correctly when the file goes to a contractor or reviewer on Bluebeam, Acrobat, Foxit, or any compliant PDF tool. Pricing is €12.99/month or €79.99/year — Mac and Windows, 14-day trial, no credit card.

Vector stamps scale cleanly
SVG-based stamps stay crisp at any zoom level — no pixelation when the recipient zooms in.
Built-in stamp library
Approved, Revised, Draft, For Review, As Built, Confidential — common cases ready to use.
Custom firm stamps
Create a custom stamp from any image or text; reuse it across projects.
Snap-to-grid placement
Stamps land consistently on the same position across a multi-page drawing set.
Stamps that travel correctly
Standard PDF annotations render correctly on Bluebeam, Acrobat, Foxit on the recipient side.

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Ncored vs free online stamp tools vs Adobe Acrobat

Free online PDF stamp services should generally not be used for confidential project drawings — the file is uploaded to a third party, the stamp quality is often low resolution, and the result may not travel cleanly to downstream viewers. Adobe Acrobat Pro has a strong stamp tool with both vector and image support; it handles the workflow well at the $240/year subscription cost. Bluebeam Revu has the deepest construction-specific stamp library and customization, particularly for construction-specific workflows. Ncored covers the practical middle: stamps render as standard vector or high-resolution annotations, the workflow is fast on heavy drawings (no lag when applying stamps to a 100 MB CAD PDF), and the price is well below either Adobe or Bluebeam. For pure stamping use cases on a Mac at small studio scale, Ncored fits cleanly.

Frequently Asked Questions

Can I create a custom stamp with my firm's logo?
Yes. Import any image (PNG, JPG, SVG) or type text directly into the custom stamp dialog. The stamp is saved to your library and reusable across projects.
Will my stamps render correctly when I send the PDF to a contractor on Bluebeam?
Yes. Ncored's stamps are written as standard PDF annotations — Bluebeam, Acrobat, Foxit all render them correctly with the same visual quality.
Do vector stamps stay crisp at deep zoom levels?
Yes. Vector stamps (SVG-based) render at any resolution without pixelation. Image-based stamps depend on the source image resolution; for crispness at high zoom, use vector or high-resolution PNG sources.
Can I stamp every page of a multi-page PDF at once?
Yes. Apply a stamp once and use the 'Apply to all pages' option, or select specific pages from the thumbnail panel and apply the stamp to the selection only.
Is the stamp permanent — can the recipient remove it?
By default the stamp is an annotation that can be moved or deleted by the recipient. To make the stamp permanent (flattened into the PDF page content), use 'Flatten annotations' before saving. Flattened stamps cannot be removed by any viewer.