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— Setup walkthrough

Choose where your watermark appears on the PDF

The watermark's position, rotation, opacity, colour and font size are all controlled from a single Settings → PDF Watermarking page. The diagonal stamp and the page-bottom footer each take their own font size and opacity. Three independent layers — diagonal stamp, footer text, invisible forensic marker — can be combined or used alone.

Before you start

Open Settings → PDF Watermarking in the Alva admin. Watermarking is paid-plan only. The choices on this page are the shop defaults applied to every watermark-enabled product. Each product can keep Use shop setting or override the page-selection setting for that specific product.

The three layers

Alva Digital Downloads composes the watermark from three layers, each toggled on or off independently:

  • Visible stamp — the large text overlay positioned on the page (the main watermark customers see).
  • Footer text — a smaller, single-line piece of text running along the bottom of each stamped page.
  • Forensic marker — an invisible identifier embedded in the PDF structure so leaked copies can be traced to the original buyer. Carries the marker even when both visible layers are off.

Combine them however suits the store. Most setups use visible stamp plus forensic marker; some prefer footer text alone for a less intrusive look.

Position presets

Pick one position for the visible stamp from the preset list. Each option places the text in a fixed region of each stamped page:

  • Top left, Top centre, Top right — first line of each stamped page.
  • Middle left, Middle centre, Middle right — vertical centre.
  • Bottom left, Bottom centre, Bottom right — above the footer text.
  • Diagonal — large diagonal stamp running from bottom-left corner to top-right corner. The default. Hardest to crop out.
  • Diagonal reverse — same idea but from top-left to bottom-right.
  • Tiled grid — repeats the text across the whole page in a regular pattern. Use when even partial copies should still carry the watermark.

Page selection

Use page selection to decide which pages receive the visible stamp and footer. The shop default lives in Settings → PDF Watermarking; each product can either keep Use shop setting or set its own selection.

  • All pages — stamp every page in the PDF.
  • First N pages — stamp the opening pages, such as the cover and introduction.
  • Last N pages — stamp the final pages, such as appendices or license pages.
  • Every Nth page — stamp page 1, then every Nth page after that.
  • Custom pages — enter pages and ranges such as 1-3, 7, 40-. Open-ended ranges run to the end of the PDF.

Stamping fewer pages can make very long PDFs finish faster. The invisible forensic marker still stays embedded in the stamped copy, even when the visible layers only appear on a subset of pages.

Opacity

The opacity slider runs from 0% (invisible) to 100% (solid). Default is 0.3 (30%). Lower opacity keeps the document readable underneath the stamp; higher opacity makes the watermark dominant. The forensic-marker layer is unaffected by this slider — invisibility is structural, not visual.

Colour and font size

The colour picker accepts any hex value. The default is a light grey that reads against most page backgrounds without dominating. Font size accepts any numeric point value and defaults to a size proportional to common A4 and Letter PDFs. Increase for image-heavy pages where the watermark sits over photos.

Preview

The live preview pane on the right side of the settings page shows the current position, opacity, colour, font size and template using sample test data. The preview is a CSS mock, not a true PDF render — colours and font sizes may differ by a few pixels in the actual output. To confirm the real result, opt one product in and place a test order against yourself.

Note

The visible stamp uses one of the nine static positions, the tiled grid, or one of the two diagonal rotations — pick one. Diagonal and Top right cannot be combined on the same layer. To stack multiple visual elements, use the footer text layer alongside the stamp layer.

Frequently asked questions

Which position is hardest for a customer to crop out of a screenshot?

Diagonal rotation across the page centre, followed by the tiled grid. Both touch every region of the visible area, so cropping to a sub-region of a single page still leaves part of the watermark visible. Corner presets are the easiest to crop out — choose them only when the watermark is informational rather than anti-leak.

Can I turn off the visible stamp and only embed the invisible forensic marker?

Yes. Turn off the visible-stamp layer and the footer-text layer, then leave the forensic-marker layer on. Customers see no visible change to the PDF, but every copy still carries a unique invisible identifier that ties it back to the original buyer if it surfaces elsewhere.

What font size should I pick for the diagonal stamp?

Start with the default, run a test order against yourself, and adjust based on the result. Larger fonts dominate the page but are harder to ignore; smaller fonts blend in but reduce the deterrent effect. Common values land between 36 and 72 points.

See also

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Last updated 2026-07-25