Are my PDFs uploaded to a server?

No. All processing is done locally in your browser using pdf-lib. Your files never leave your device.

Can I add a watermark and page numbers at the same time?

Yes - that is the point of this tool. Enable both overlays, configure each independently, and they are applied together in a single pass with one download.

Can I control the opacity of the watermark?

Yes. The opacity slider goes from 5% (nearly invisible) to 100% (fully opaque). Around 20-30% is typical for background watermarks that keep the content readable.

What page-number formats are available?

Plain numbers (1, 2 …), fractions (1 / 10), "Page N", or "Page N of Total". You can also set the starting number, useful when the PDF has front matter.

Are the overlays applied to all pages?

Yes. The watermark is drawn in the same position on every page, and page numbers increment per page from your chosen starting number.

Helvetica, a standard built-in PDF font available in all PDF readers without embedding - so the file size barely grows.

PDF Stamp - Add Watermarks & Page Numbers to PDFs Online

Watermarks and page numbers in one pass

A watermark and a page number are the same operation under the hood: text drawn on top of every page at a chosen position. This tool exposes both as independent overlays with a shared live preview - enable either one alone, or both together, and download a single stamped PDF. The classic combination of "CONFIDENTIAL" diagonally across the page plus "Page N of Total" at the bottom takes one upload and one click instead of a round-trip through two separate tools. Everything runs locally using pdf-lib; nothing is uploaded.

Watermark options

Type any text up to 200 characters - "DRAFT", "DO NOT COPY", a company name - and control font size (8-144 pt), opacity (5-100%), and position. The diagonal placement rotates the text 45 degrees across the page centre, the traditional look for document-wide stamps. Keep opacity around 20-30% so the underlying content stays readable; the preview shows the effect on every page before you commit.

Page numbering options

Choose one of six positions (top or bottom; left, centre, or right), a format (plain 1, 1 / 10, Page 1, or Page 1 of 10), the font size, and the starting number. A custom start is handy when the file is a chapter extracted from a longer work and needs to continue that document's numbering, or when a cover page means numbering should begin at 0.

How the overlay is drawn

Both overlays are drawn with the built-in Helvetica font, so no font data needs embedding and the output file barely grows. The text is added on top of the existing page content as a normal PDF text object - it prints, it survives re-saving, and (in the watermark's case) it is intentionally not trivial to remove without a PDF editor. Existing content is never re-encoded, so there is no quality loss.

Limitations to know about

Encrypted PDFs must be unlocked before stamping. The watermark applies the same position and size on every page; a page that is much smaller than the rest may clip a very large watermark, so check the preview when your document mixes page sizes. If a page already carries a visual page number, the new numbers are drawn over the page as-is - pick a different corner to avoid overlap.