About

PDF Watermark

Stamp a diagonal text watermark across every page of a PDF — "DRAFT", "CONFIDENTIAL", your name, or anything else. Runs in your browser; the PDF never leaves your device.

Drop PDF files here or
  1. Drop one or many PDFs.
  2. Type the watermark text — "DRAFT", "CONFIDENTIAL", a client name, an NDA tag, whatever. Preset buttons fill in the common ones.
  3. Adjust size, angle, colour, and opacity. 25% opacity at 45° is the classic diagonal stamp.
  4. Click Watermark all. Download each output individually or grab everything as a ZIP.
What does it do?

The tool loads each PDF, measures every page, and draws your text across the centre of each page at the angle you picked. The text sits on top of the existing content; the opacity slider controls how much it obscures the page underneath. Nothing is uploaded — all drawing happens in your browser using pdf-lib.

Example

Input:    proposal-v3.pdf (12 pages)
Settings: text="CONFIDENTIAL", size 72, angle 45°,
          colour #c0392b, opacity 25%
Output:   proposal-v3-watermarked.pdf (12 pages, stamped)

Common errors and pitfalls

Most issues come from the watermark not being laid out the way you expected. A few common pitfalls:

  • Watermark too small to read. The default size (72pt) fits "DRAFT" across a letter-sized page at 45°. Longer text like "PROPERTY OF ACME CORP" needs a smaller size or a smaller angle to fit without running off the page.
  • Watermark too opaque, can't read the text. Drop the opacity to 15–20% for a subtle tint. 100% opacity turns the watermark into a solid banner that blocks the content underneath.
  • Colour picker shows the wrong colour. The picker uses sRGB; PDF viewers may render slightly differently depending on their colour management. If exact brand colour matters, pick the value you know renders correctly in your target viewer rather than the one that looks right on screen.
  • "DRAFT" stamped on a final document. The tool doesn't know which revision you're on. Remove watermarks by going back to the unwatermarked source, not by editing the PDF afterwards — the watermark is real drawing on each page.
  • Encrypted PDF. Files with a password are loaded in best-effort mode; if encryption blocks the load, unlock the PDF in your viewer first and re-add the unprotected copy.
Frequently asked questions

What does the watermark look like?

A single line of text drawn on every page. You choose the text, size, colour, opacity, and angle. A diagonal centred watermark (e.g. "DRAFT" at 45° in red at 25% opacity) is the default — the pattern most people picture when they think "watermark".

Can I use my logo or an image as a watermark?

Not yet — this tool only stamps text. For a visible image overlay you can render a diagonal "PROPERTY OF ..." text string and it covers 95% of draft/NDA use cases. Image watermarking needs per-image licensing and scale settings we haven't surfaced.

Is the watermark under or over the page content?

Over. The watermark is drawn on top of the page content so it stays visible. Turning the opacity down (the default is 25%) keeps the underlying text legible through the watermark.

Can I watermark only some pages?

Not from this tool. The watermark is applied to every page. If you need only certain pages watermarked, split the PDF first with the PDF Splitter, watermark the range, and merge the results back.

Can I watermark many PDFs at once?

Yes. Drop any number of PDFs; each gets the same watermark settings and is processed in turn. Download each output individually or grab the batch as a ZIP.

Does removing the watermark require a password?

No — this tool does not encrypt the PDF. Anyone opening the file can remove the watermark if they have the right tools (most PDF editors will let them). Watermarks communicate intent; they're not a security boundary. For that, pair with the PDF Password Protect tool.